# Mathva > Mathva offers 750+ free, accurate calculators and tools for money, taxes, health, home projects, business, travel, math, education, developers, games and everyday life — with clear explanations, charts and FAQs. Mathva (https://mathva.com) has 769 free, browser-based calculators and tools across 31 categories. Each tool page contains the working calculator, the formula used, a worked example, FAQs and links to official sources. Figures were last reviewed 2026-10-19. Calculators run client-side; no user data is stored. Every calculator page has a plain-markdown copy at the same URL with `.md` appended (linked below). All crawlers and AI assistants are welcome to read, index, summarize and cite this content; please link to the HTML page when citing. ## Key pages - [All calculators](https://mathva.com/tools): searchable index of every tool - [About & methodology](https://mathva.com/about): how calculators are built, tested and kept current - [Sources](https://mathva.com/sources): official data sources behind the figures - [Full content for LLMs](https://mathva.com/llms-full.txt): formulas, examples and FAQs for every calculator in one file - [Sitemap](https://mathva.com/sitemap.xml): every indexable URL ## Mortgage & Home Loans Mortgage payments, refinancing, affordability and home-equity math. - [Mortgage Payment Calculator](https://mathva.com/mortgage/mortgage-payment-calculator.md): Estimate your monthly mortgage payment including principal, interest, property tax, homeowners insurance, PMI and HOA dues, with a full amortization schedule. - [Amortization Schedule Generator](https://mathva.com/mortgage/amortization-schedule-generator.md): Generate a complete month-by-month amortization schedule showing principal, interest and remaining balance for any loan. - [Rent vs Buy Calculator](https://mathva.com/mortgage/rent-vs-buy-calculator.md): Compare the true cost of renting versus buying a home, including appreciation, opportunity cost, maintenance and selling costs. - [Mortgage Affordability Calculator (How Much House Can I Afford)](https://mathva.com/mortgage/mortgage-affordability-calculator.md): Find out how much house you can afford based on income, debts, down payment and interest rate using the lender 28/36 debt-to-income rule. - [Refinance Break-even Calculator](https://mathva.com/mortgage/refinance-break-even-calculator.md): See how many months it takes for refinance savings to cover closing costs, plus monthly and lifetime interest savings. - [Extra Payment Mortgage Payoff Calculator](https://mathva.com/mortgage/extra-payment-mortgage-payoff-calculator.md): Calculate how much interest and time you save by making extra monthly, yearly or lump-sum mortgage payments. - [Biweekly Mortgage Payment Calculator](https://mathva.com/mortgage/biweekly-mortgage-payment-calculator.md): Compare monthly vs biweekly mortgage payments and see how much interest and time you save with 26 half-payments a year. - [ARM vs Fixed Rate Comparison Tool](https://mathva.com/mortgage/arm-vs-fixed-rate-comparison-tool.md): Compare an adjustable-rate mortgage with a fixed-rate loan over the years you plan to keep it, including rate caps and resets. - [PMI Removal Date Calculator](https://mathva.com/mortgage/pmi-removal-date-calculator.md): Find the exact month your private mortgage insurance (PMI) can be cancelled at 80% LTV or drops off automatically at 78%. - [Mortgage Points Buy-down Calculator](https://mathva.com/mortgage/mortgage-points-buy-down-calculator.md): Decide whether buying mortgage discount points is worth it by calculating the break-even month and net savings. - [Down Payment Savings Timeline](https://mathva.com/mortgage/down-payment-savings-timeline.md): Calculate how long it will take to save for a down payment and closing costs, including interest on your savings. - [Closing Cost Estimator by US State](https://mathva.com/mortgage/closing-cost-estimator-by-us-state.md): Estimate buyer closing costs by state — lender fees, title insurance, transfer and mortgage taxes, attorney fees, prepaids and escrow — plus cash needed to close. - [HELOC Payment Calculator](https://mathva.com/mortgage/heloc-payment-calculator.md): Estimate HELOC payments during the interest-only draw period and the fully amortizing repayment period. - [Home Equity Available Calculator](https://mathva.com/mortgage/home-equity-available-calculator.md): Calculate your home equity and how much you can borrow with a HELOC, home equity loan or cash-out refinance. - [Reverse Mortgage Estimator](https://mathva.com/mortgage/reverse-mortgage-estimator.md): Reverse mortgage calculator: estimate HECM proceeds by age, home value, mortgage balance and interest rate, including MIP, fees, lifetime payments and loan growth. - [UK Stamp Duty Calculator](https://mathva.com/mortgage/uk-stamp-duty-calculator.md): Calculate UK Stamp Duty Land Tax for home movers, first-time buyers and additional properties in England and Northern Ireland. - [Canada Land Transfer Tax Calculator](https://mathva.com/mortgage/canada-land-transfer-tax-calculator.md): Estimate Canadian land transfer tax for Ontario, Toronto and British Columbia, including first-time buyer rebates. - [UK Mortgage Overpayment Calculator](https://mathva.com/mortgage/uk-mortgage-overpayment-calculator.md): See how overpaying your UK mortgage shortens the term and cuts interest, and check your penalty-free overpayment allowance. - [Second Mortgage Calculator](https://mathva.com/mortgage/second-mortgage-calculator.md): Calculate the payment, total interest and combined loan-to-value for a second mortgage or home equity loan. - [Mortgage Recast Calculator](https://mathva.com/mortgage/mortgage-recast-calculator.md): See how much a mortgage recast lowers your monthly payment after a lump-sum principal payment. - [Loan-to-value (LTV) Ratio Calculator](https://mathva.com/mortgage/loan-to-value-ratio-calculator.md): Calculate your loan-to-value (LTV) ratio and how much you need to pay down to reach 80% and avoid PMI. - [Debt-to-income (DTI) Ratio Calculator](https://mathva.com/mortgage/debt-to-income-ratio-calculator.md): Calculate your front-end and back-end debt-to-income ratio and see how lenders will view it. - [Bridge Loan Calculator](https://mathva.com/mortgage/bridge-loan-calculator.md): Estimate how much you can borrow with a bridge loan and what it costs to buy a new home before selling your current one. - [FHA Loan Limit Lookup by County](https://mathva.com/mortgage/fha-loan-limit-lookup-by-county.md): FHA loan limit lookup for 2026 by county: estimate your county’s limit for 1–4 unit homes, see the floor and ceiling, and check the max price with 3.5% down. - [VA Loan Entitlement Calculator](https://mathva.com/mortgage/va-loan-entitlement-calculator.md): Calculate your remaining VA loan entitlement, the maximum loan with zero down and the VA funding fee. ## Auto & Vehicle Car loans, leases, fuel costs, EV savings and vehicle specs. - [Car Loan Payment Calculator](https://mathva.com/auto/car-loan-payment-calculator.md): Calculate your monthly car payment including sales tax, fees, down payment and trade-in, plus total interest and an amortization schedule. - [Car Affordability Calculator](https://mathva.com/auto/car-affordability-calculator.md): Find out how much car you can afford from your income, running costs, down payment and loan rate using the 20/4/10 rule. - [Lease vs Buy Calculator](https://mathva.com/auto/lease-vs-buy-calculator.md): Compare the true cost of leasing versus buying a car over the same period, including equity and resale value. - [Car Lease Payment Calculator](https://mathva.com/auto/car-lease-payment-calculator.md): Calculate a car lease payment from MSRP, negotiated price, residual value, money factor, term and sales tax. - [Auto Loan Refinance Savings Calculator](https://mathva.com/auto/auto-loan-refinance-savings-calculator.md): See how much you could save by refinancing your auto loan to a lower rate, including fees and term changes. - [Car Depreciation Calculator](https://mathva.com/auto/car-depreciation-calculator.md): Estimate how much value your car will lose each year and what it will be worth when you sell or trade it in. - [Total Cost of Ownership Calculator](https://mathva.com/auto/total-cost-of-ownership-calculator.md): Calculate the true total cost of owning a car: depreciation, fuel, insurance, maintenance, fees and loan interest. - [Gas Cost per Trip Calculator](https://mathva.com/auto/gas-cost-per-trip-calculator.md): Work out how much fuel a road trip will cost based on distance, fuel economy and gas prices, split between passengers. - [MPG Calculator](https://mathva.com/auto/mpg-calculator.md): Calculate your real-world miles per gallon from a fill-up, plus L/100 km and fuel cost per mile. - [EV vs Gas Savings Calculator](https://mathva.com/auto/ev-vs-gas-savings-calculator.md): Compare EV charging costs with gasoline and find the payback period on the extra cost of an electric vehicle. - [EV Charging Cost Calculator](https://mathva.com/auto/ev-charging-cost-calculator.md): Calculate the cost of charging an electric car at home or a public charger, including charging losses and cost per mile. - [Early Car Payoff Calculator](https://mathva.com/auto/early-car-payoff-calculator.md): See how extra monthly or lump-sum payments shorten your car loan and reduce total interest. - [Trade-in Equity Calculator](https://mathva.com/auto/trade-in-equity-calculator.md): Calculate your trade-in equity: whether your car is worth more or less than you owe, including the sales tax credit. - [Negative Equity Rollover Calculator](https://mathva.com/auto/negative-equity-rollover-calculator.md): See the real cost of rolling negative equity from your current car loan into a new car loan. - [Car Sales Tax by State Calculator](https://mathva.com/auto/car-sales-tax-by-state-calculator.md): Estimate car sales tax by state including local rates and the trade-in tax credit. - [Vehicle Registration Fee Estimator](https://mathva.com/auto/vehicle-registration-fee-estimator.md): Estimate annual vehicle registration fees by state, including value-based taxes, EV and hybrid fees, and how costs change as your car ages. - [IRS Mileage Reimbursement Calculator](https://mathva.com/auto/irs-mileage-reimbursement-calculator.md): Calculate mileage reimbursement or tax deduction using the 2026 IRS standard mileage rates for business, medical and charity driving. - [Road Trip Cost Splitter](https://mathva.com/auto/road-trip-cost-splitter.md): Split road trip costs fairly between friends, including fuel, tolls, lodging and food. - [Towing Capacity Checker](https://mathva.com/auto/towing-capacity-checker.md): Check whether your vehicle can safely tow a trailer, including the 80% rule, tongue weight and payload. - [Tire Size Comparison Calculator](https://mathva.com/auto/tire-size-comparison-calculator.md): Compare two tire sizes side by side: diameter, sidewall, circumference, revolutions per mile and speedometer error. - [Gear Ratio / Speedometer Error Calculator](https://mathva.com/auto/gear-ratio-speedometer-error-calculator.md): Calculate speedometer error and engine RPM after changing tire size or axle gear ratio, and find the ratio that restores factory gearing. - [0-60 Time Estimator from HP and Weight](https://mathva.com/auto/0-60-time-estimator-from-hp-and-weight.md): Estimate 0–60 mph and quarter-mile times from horsepower, weight and drivetrain. - [Horsepower to Torque Converter](https://mathva.com/auto/horsepower-to-torque-converter.md): Convert horsepower to torque or torque to horsepower at any RPM, with kW and N·m conversions. - [MPG to L/100km Converter](https://mathva.com/auto/mpg-to-l-100km-converter.md): Convert fuel economy between US mpg, UK (imperial) mpg, L/100 km and km/L. - [Car Insurance Deductible Break-even Calculator](https://mathva.com/auto/car-insurance-deductible-break-even-calculator.md): Decide whether a higher car insurance deductible is worth it by calculating the claim-free break-even period. ## Personal Loans & Debt Debt payoff plans, credit cards, personal and student loans. - [Debt Snowball Calculator](https://mathva.com/loans-debt/debt-snowball-calculator.md): Build a debt snowball plan: pay off your smallest balances first and see your debt-free date and total interest. - [Credit Card Payoff Calculator](https://mathva.com/loans-debt/credit-card-payoff-calculator.md): Find out how long it takes to pay off a credit card, or the monthly payment needed to be debt-free by a target date. - [EMI Calculator](https://mathva.com/loans-debt/emi-calculator.md): EMI calculator for home, car and personal loans in India: monthly EMI, total interest, year-wise amortization schedule and savings from prepayments. - [Personal Loan Payment Calculator](https://mathva.com/loans-debt/personal-loan-payment-calculator.md): Calculate personal loan payments, total interest and the true APR including origination fees. - [Debt Avalanche Calculator](https://mathva.com/loans-debt/debt-avalanche-calculator.md): Plan your debt payoff with the avalanche method — highest interest rate first — to pay the least interest possible. - [Minimum Payment Trap Calculator](https://mathva.com/loans-debt/minimum-payment-trap-calculator.md): See how long minimum credit card payments take and how much interest they cost compared with a fixed payment. - [Balance Transfer Savings Calculator](https://mathva.com/loans-debt/balance-transfer-savings-calculator.md): Calculate how much a 0% balance transfer card saves after the transfer fee, and whether you’ll pay it off before the promo ends. - [APR to Monthly Interest Converter](https://mathva.com/loans-debt/apr-to-monthly-interest-converter.md): Convert an APR into monthly and daily interest rates, the effective annual rate, and dollar interest on your balance. - [Side-by-side Loan Comparison Tool](https://mathva.com/loans-debt/side-by-side-loan-comparison-tool.md): Compare two loan offers side by side: monthly payment, total interest, fees and true APR. - [Payday Loan True Cost Calculator](https://mathva.com/loans-debt/payday-loan-true-cost-calculator.md): Reveal the true APR and total cost of a payday loan, including rollovers, compared with a credit card. - [Student Loan Payoff Calculator](https://mathva.com/loans-debt/student-loan-payoff-calculator.md): Calculate student loan payments and see how extra payments shorten the payoff date and cut interest. - [Student Loan Refinance Calculator](https://mathva.com/loans-debt/student-loan-refinance-calculator.md): See how much refinancing student loans saves on monthly payments and lifetime interest. - [Income-driven Repayment Estimator](https://mathva.com/loans-debt/income-driven-repayment-estimator.md): Estimate federal student loan payments under income-driven repayment, including the new Repayment Assistance Plan (RAP) and IBR. - [Debt Consolidation Calculator](https://mathva.com/loans-debt/debt-consolidation-calculator.md): Find out whether a debt consolidation loan saves money compared with paying your current debts separately. - [Prepayment Penalty Calculator](https://mathva.com/loans-debt/prepayment-penalty-calculator.md): Calculate a loan prepayment penalty and whether paying off or refinancing still saves money after the penalty. - [Interest-only vs Amortizing Comparison](https://mathva.com/loans-debt/interest-only-vs-amortizing-comparison.md): Compare interest-only and fully amortizing loan payments, the payment jump after the IO period, and total interest. - [Buy Now Pay Later True Cost Calculator](https://mathva.com/loans-debt/buy-now-pay-later-true-cost-calculator.md): Calculate the true cost and effective APR of buy now, pay later plans when late fees apply. - [Credit Utilization Calculator](https://mathva.com/loans-debt/credit-utilization-calculator.md): Calculate your overall and per-card credit utilization ratio and how much to pay down to reach 30% or 10%. - [Credit Score Impact Simulator](https://mathva.com/loans-debt/credit-score-impact-simulator.md): Credit score impact simulator: estimate how late payments, hard inquiries, new cards, utilization changes, collections, foreclosure or bankruptcy could change your score. - [Debt-free Date Calculator](https://mathva.com/loans-debt/debt-free-date-calculator.md): Find your exact debt-free date based on your total debt, interest rate and monthly payment. - [Cosigner Risk Calculator](https://mathva.com/loans-debt/cosigner-risk-calculator.md): Understand the financial risk of cosigning a loan: your full liability, and the impact on your own debt-to-income ratio. ## Investing & Retirement Compound growth, retirement, FIRE, dividends, bonds and trading math. - [Compound Interest Calculator](https://mathva.com/investing-retirement/compound-interest-calculator.md): Calculate compound interest with regular monthly contributions, any compounding frequency and optional inflation adjustment. - [Retirement Savings Calculator](https://mathva.com/investing-retirement/retirement-savings-calculator.md): See whether you are on track for retirement and how much more to save each month to reach your income goal. - [PPF Calculator](https://mathva.com/investing-retirement/ppf-calculator.md): PPF calculator: calculate Public Provident Fund maturity value, tax-free interest and year-by-year balance at 7.1% for 15 years or longer. - [Monthly Investment / SIP Calculator](https://mathva.com/investing-retirement/monthly-investment-sip-calculator.md): Estimate the future value of a monthly investment plan (SIP), with optional annual step-up and lump sum. - [401k Growth Calculator](https://mathva.com/investing-retirement/401k-growth-calculator.md): Project your 401(k) balance at retirement with your contributions, employer match, raises and investment returns. - [401k Employer Match Calculator](https://mathva.com/investing-retirement/401k-employer-match-calculator.md): Calculate your 401(k) employer match and how much free money you leave on the table by contributing too little. - [Roth vs Traditional IRA Comparison](https://mathva.com/investing-retirement/roth-vs-traditional-ira-comparison.md): Compare Roth and traditional IRA or 401(k) contributions to see which leaves more after-tax money in retirement. - [Roth Conversion Tax Calculator](https://mathva.com/investing-retirement/roth-conversion-tax-calculator.md): Estimate the federal and state income tax owed on a Roth IRA conversion and the bracket it pushes you into. - [Required Minimum Distribution (RMD) Calculator](https://mathva.com/investing-retirement/required-minimum-distribution-calculator.md): Calculate your required minimum distribution (RMD) using the IRS Uniform Lifetime Table and project future RMDs. - [Social Security Benefit Estimator](https://mathva.com/investing-retirement/social-security-benefit-estimator.md): Estimate your Social Security retirement benefit and compare claiming at every age from 62 to 70. - [FIRE Number Calculator](https://mathva.com/investing-retirement/fire-number-calculator.md): Calculate your FIRE (financial independence, retire early) number and how long it will take to reach it. - [Safe Withdrawal Rate Calculator](https://mathva.com/investing-retirement/safe-withdrawal-rate-calculator.md): Test how long your retirement portfolio lasts at a given withdrawal rate and find the maximum sustainable withdrawal. - [Coast FIRE Calculator](https://mathva.com/investing-retirement/coast-fire-calculator.md): Find your Coast FIRE number — the amount you need invested now so growth alone funds retirement — and when you can stop saving. - [Dividend Income Calculator](https://mathva.com/investing-retirement/dividend-income-calculator.md): Project dividend income from a stock portfolio with dividend growth, reinvestment and monthly additions. - [DRIP Reinvestment Calculator](https://mathva.com/investing-retirement/drip-reinvestment-calculator.md): Compare a dividend reinvestment plan (DRIP) with taking dividends in cash over time. - [Stock Profit/loss Calculator](https://mathva.com/investing-retirement/stock-profit-loss-calculator.md): Calculate profit or loss, return percentage, break-even price and estimated tax on a stock trade. - [Cost Basis / Average Down Calculator](https://mathva.com/investing-retirement/cost-basis-average-down-calculator.md): Calculate your average cost per share after buying at different prices (averaging down or up) and your unrealized gain. - [Position Size Calculator](https://mathva.com/investing-retirement/position-size-calculator.md): Calculate how many shares to buy based on account size, risk percentage and stop-loss distance. - [Risk-reward Ratio Calculator](https://mathva.com/investing-retirement/risk-reward-ratio-calculator.md): Calculate the risk-reward ratio of a trade and the win rate needed to break even. - [Options Profit Calculator](https://mathva.com/investing-retirement/options-profit-calculator.md): Calculate profit, loss and break-even for buying or selling call and put options at expiration, with a payoff chart. - [Covered Call Yield Calculator](https://mathva.com/investing-retirement/covered-call-yield-calculator.md): Calculate covered call returns: static yield, return if called, annualized yield and downside protection. - [Bond Yield to Maturity Calculator](https://mathva.com/investing-retirement/bond-yield-to-maturity-calculator.md): Calculate a bond’s yield to maturity (YTM) and current yield from its price, coupon and time to maturity. - [CD Ladder Calculator](https://mathva.com/investing-retirement/cd-ladder-calculator.md): Build a CD ladder: split your savings across CD terms, see the average yield and interest earned on each rung. - [Treasury Bill Yield Calculator](https://mathva.com/investing-retirement/treasury-bill-yield-calculator.md): Calculate Treasury bill discount yield, bond-equivalent yield and APY from the price and days to maturity. - [Inflation-adjusted Return Calculator](https://mathva.com/investing-retirement/inflation-adjusted-return-calculator.md): Convert a nominal investment return into a real, inflation-adjusted return and see its value in today’s dollars. - [CAGR Calculator](https://mathva.com/investing-retirement/cagr-calculator.md): Calculate the compound annual growth rate (CAGR) between a starting and ending value over any number of years. - [Portfolio Rebalancing Calculator](https://mathva.com/investing-retirement/portfolio-rebalancing-calculator.md): Rebalance your portfolio: see exactly how much to buy or sell of each holding to return to your target allocation. - [Expense Ratio Drag Calculator](https://mathva.com/investing-retirement/expense-ratio-drag-calculator.md): See how much fund expense ratios cost over time by comparing two funds with different fees. - [Capital Gains Tax Calculator](https://mathva.com/investing-retirement/capital-gains-tax-calculator.md): Estimate federal and state capital gains tax on stocks, property or other assets for short- and long-term gains using 2026 brackets. - [Wash Sale Checker](https://mathva.com/investing-retirement/wash-sale-checker.md): Check whether a trade triggers the IRS wash sale rule and calculate the disallowed loss and adjusted cost basis. - [Annuity Payout Calculator](https://mathva.com/investing-retirement/annuity-payout-calculator.md): Calculate the income from a fixed-period annuity based on principal, interest rate and payout period. - [Pension Lump Sum vs Annuity Calculator](https://mathva.com/investing-retirement/pension-lump-sum-vs-annuity-calculator.md): Compare a pension lump sum with monthly annuity payments using present value and the annuity’s implied return. - [Millionaire Timeline Calculator](https://mathva.com/investing-retirement/millionaire-timeline-calculator.md): Find out when you will become a millionaire based on your savings, monthly investing and expected return. - [Rule of 72 Calculator](https://mathva.com/investing-retirement/rule-of-72-calculator.md): Use the Rule of 72 to estimate how long money takes to double at a given interest rate, with the exact answer for comparison. - [Dollar Cost Averaging Backtester](https://mathva.com/investing-retirement/dollar-cost-averaging-backtester.md): Dollar cost averaging backtester: see how monthly investing in the S&P 500 would have grown over any period since 1975, versus a lump sum, with inflation-adjusted value. - [Emergency Fund Calculator](https://mathva.com/investing-retirement/emergency-fund-calculator.md): Calculate how big your emergency fund should be and how long it will take to build it. - [EPF Calculator](https://mathva.com/investing-retirement/epf-calculator.md): EPF calculator: project your Employees’ Provident Fund balance at retirement from basic salary, raises and the 8.25% interest rate, with EPS split. ## Tax (Country Specific) US, UK, Canada and Australia income, payroll, sales and capital gains tax. - [Paycheck / Take-home Pay Calculator](https://mathva.com/tax/paycheck-take-home-pay-calculator.md): Calculate your take-home pay per paycheck after federal tax, Social Security, Medicare, state tax, 401(k) and health premiums. - [Sales Tax Calculator by ZIP Code](https://mathva.com/tax/sales-tax-calculator-by-zip-code.md): Sales tax calculator by ZIP code: find the state and estimated combined state and local sales tax rate for any U.S. ZIP, and calculate tax on a purchase. - [UK Take-home Pay Calculator](https://mathva.com/tax/uk-take-home-pay-calculator.md): Work out your UK take-home pay per month and week for 2026/27 after Income Tax, National Insurance and pension. - [Canada Income Tax Calculator by Province](https://mathva.com/tax/canada-income-tax-calculator-by-province.md): Canada income tax calculator 2026 by province: federal and provincial tax, CPP/QPP, EI, take-home pay, average and marginal rates, with a province comparison. - [India Income Tax Calculator (Old vs New Regime)](https://mathva.com/tax/india-income-tax-calculator-old-vs-new-regime.md): India income tax calculator FY 2026-27: compare old vs new tax regime with 80C, 80D, HRA, home loan interest, NPS, rebate, surcharge and cess. - [GST Calculator India](https://mathva.com/tax/gst-calculator-india.md): GST calculator India: add or remove GST at 5%, 18% or 40% and split tax into CGST, SGST or IGST for intra-state and inter-state supplies. - [US Federal Income Tax Estimator](https://mathva.com/tax/us-federal-income-tax-estimator.md): Estimate your 2026 US federal income tax with current brackets, standard or itemized deductions, child tax credit and capital gains. - [State Income Tax Calculator (One Page per State)](https://mathva.com/tax/state-income-tax-calculator.md): Estimate 2026 state income tax for all 50 states and DC — brackets, deductions, typical local income taxes and how your state ranks. - [W-4 Withholding Calculator](https://mathva.com/tax/w-4-withholding-calculator.md): W-4 withholding calculator: check if your paycheck withholding matches your 2026 tax, and find the Step 3 and Step 4(c) amounts to avoid owing or a big refund. - [Self-employment Tax Calculator](https://mathva.com/tax/self-employment-tax-calculator.md): Calculate 2026 self-employment tax (Social Security and Medicare) plus estimated federal income tax for freelancers and 1099 workers. - [Quarterly Estimated Tax Calculator](https://mathva.com/tax/quarterly-estimated-tax-calculator.md): Calculate quarterly estimated tax payments for 2026, including self-employment tax, due dates and the safe-harbor amount. - [1099 vs W2 Net Pay Comparison](https://mathva.com/tax/1099-vs-w2-net-pay-comparison.md): Compare W-2 salary with 1099 contractor pay after self-employment tax, expenses and benefits to find the break-even rate. - [Property Tax Estimator by County](https://mathva.com/tax/property-tax-estimator-by-county.md): Estimate annual property tax by county or state using median effective tax rates, homestead exemptions and comparisons with state and U.S. averages. - [Capital Gains Tax Bracket Calculator](https://mathva.com/tax/capital-gains-tax-bracket-calculator.md): See which 2026 long-term capital gains bracket (0%, 15% or 20%) applies to your gain and how much falls in each. - [Crypto Tax Estimator](https://mathva.com/tax/crypto-tax-estimator.md): Estimate US federal tax on cryptocurrency gains, staking and mining income using 2026 brackets. - [UK Income Tax and National Insurance Calculator](https://mathva.com/tax/uk-income-tax-and-national-insurance-calculator.md): Calculate UK Income Tax and National Insurance for 2026/27, including the Personal Allowance taper and pension contributions. - [UK VAT Calculator](https://mathva.com/tax/uk-vat-calculator.md): Add or remove UK VAT at 20%, 5% or 0% and see the net, VAT and gross amounts. - [Canada GST/HST Calculator](https://mathva.com/tax/canada-gst-hst-calculator.md): Calculate Canadian GST, HST, PST and QST for any province or territory — add tax or back it out of a total. - [Australia Income Tax Calculator](https://mathva.com/tax/australia-income-tax-calculator.md): Calculate Australian income tax for 2026–27 with the new 15% bracket, Medicare levy and low income tax offset. - [Australia GST Calculator](https://mathva.com/tax/australia-gst-calculator.md): Add or remove 10% Australian GST and see the GST amount — divide by 11 to find GST in a GST-inclusive price. - [Germany Brutto-Netto Rechner](https://mathva.com/tax/germany-brutto-netto-rechner.md): Brutto-Netto-Rechner 2026: calculate German net salary from gross by tax class — Lohnsteuer, Soli, Kirchensteuer and social insurance (KV, PV, RV, AV). - [Tax Bracket Finder](https://mathva.com/tax/tax-bracket-finder.md): Find your 2026 federal tax bracket, how far you are from the next one, and see all brackets for your filing status. - [Marginal vs Effective Tax Rate Calculator](https://mathva.com/tax/marginal-vs-effective-tax-rate-calculator.md): Compare your marginal and effective federal tax rates and see how progressive brackets apply to your income. - [Standard vs Itemized Deduction Comparison](https://mathva.com/tax/standard-vs-itemized-deduction-comparison.md): Decide whether to itemize or take the standard deduction for 2026, with the new SALT cap and charitable floor. - [Home Office Deduction Calculator](https://mathva.com/tax/home-office-deduction-calculator.md): Compare the simplified and regular home office deduction methods and estimate your tax savings as a self-employed worker. - [Charitable Donation Tax Savings Calculator](https://mathva.com/tax/charitable-donation-tax-savings-calculator.md): Estimate how much tax you save by donating to charity under the 2026 rules, whether or not you itemize. - [Child Tax Credit Estimator](https://mathva.com/tax/child-tax-credit-estimator.md): Estimate your 2026 child tax credit, the phase-out for higher incomes and the refundable portion. - [Dependent Care Credit Calculator](https://mathva.com/tax/dependent-care-credit-calculator.md): Child and dependent care credit calculator for 2026: estimate your credit with the new 50%–20% rates, $3,000/$6,000 expense limits and dependent care FSA offset. - [Tax Refund Estimator](https://mathva.com/tax/tax-refund-estimator.md): Estimate your 2026 federal tax refund or balance due from wages, withholding, deductions and child tax credit. - [Overtime Tax Impact Calculator](https://mathva.com/tax/overtime-tax-impact-calculator.md): See how much overtime you actually keep after tax, including the new federal “no tax on overtime” deduction for 2025–2028. - [Bonus Withholding Calculator](https://mathva.com/tax/bonus-withholding-calculator.md): Calculate how much of your bonus you take home after the 22% federal supplemental withholding, FICA and state tax. - [Freelancer Tax Set-aside Calculator](https://mathva.com/tax/freelancer-tax-set-aside-calculator.md): Find out what percentage of freelance income to set aside for taxes each month, including self-employment and state tax. - [HRA Exemption Calculator](https://mathva.com/tax/hra-exemption-calculator.md): HRA exemption calculator: find tax-free and taxable house rent allowance from basic salary, HRA, rent paid and metro or non-metro city. ## Insurance Life, health, home, disability and umbrella coverage needs. - [Life Insurance Needs Calculator](https://mathva.com/insurance/life-insurance-needs-calculator.md): Calculate how much life insurance you need with the DIME method: debts, income, mortgage and education, minus existing resources. - [Term vs Whole Life Comparison](https://mathva.com/insurance/term-vs-whole-life-comparison.md): Compare term and whole life insurance with the “buy term and invest the difference” strategy. - [Health Insurance Premium Estimator](https://mathva.com/insurance/health-insurance-premium-estimator.md): Estimate 2026 ACA marketplace health insurance premiums by age, household income and plan level, including premium tax credits and cost after subsidies. - [HSA Contribution and Growth Calculator](https://mathva.com/insurance/hsa-contribution-and-growth-calculator.md): Project HSA growth with 2026 contribution limits, employer contributions, tax savings and medical withdrawals. - [FSA Planning Calculator](https://mathva.com/insurance/fsa-planning-calculator.md): Plan your FSA contribution: see your tax savings, the 2026 limit and how much you might forfeit under use-it-or-lose-it. - [Deductible vs Premium Break-even Calculator](https://mathva.com/insurance/deductible-vs-premium-break-even-calculator.md): Compare two health plans’ total yearly cost — premiums plus deductible and coinsurance — at any level of medical use. - [Car Insurance Estimate Calculator](https://mathva.com/insurance/car-insurance-estimate-calculator.md): Car insurance cost estimator: estimate your auto insurance premium by state, age, driving record, credit, vehicle, coverage level and deductible. - [Home Insurance Coverage Calculator](https://mathva.com/insurance/home-insurance-coverage-calculator.md): Estimate how much homeowners insurance you need: dwelling, other structures, personal property, loss of use and liability. - [Renters Insurance Calculator](https://mathva.com/insurance/renters-insurance-calculator.md): Estimate how much renters insurance coverage you need by adding up the value of your belongings. - [Disability Insurance Needs Calculator](https://mathva.com/insurance/disability-insurance-needs-calculator.md): Calculate how much disability insurance you need to replace your income if you can’t work, and estimate the premium range. - [Pet Insurance Cost Estimator](https://mathva.com/insurance/pet-insurance-cost-estimator.md): Pet insurance cost estimator for dogs and cats: estimate monthly premiums by age, breed size, deductible, reimbursement, annual limit and location. - [Travel Insurance Cost Estimator](https://mathva.com/insurance/travel-insurance-cost-estimator.md): Estimate travel insurance cost as a percentage of trip cost for basic, comprehensive and cancel-for-any-reason plans. - [Umbrella Policy Coverage Calculator](https://mathva.com/insurance/umbrella-policy-coverage-calculator.md): Calculate how much umbrella liability insurance you need based on your net worth, income and risk factors. - [Medicare Cost Estimator](https://mathva.com/insurance/medicare-cost-estimator.md): Estimate your yearly Medicare costs with 2026 Part B premiums and deductible, Part D, Medigap and out-of-pocket spending. - [COBRA Cost Calculator](https://mathva.com/insurance/cobra-cost-calculator.md): Calculate your COBRA health insurance premium after leaving a job and compare it with a marketplace plan. ## Salary, Career & HR Hourly/salary conversion, overtime, raises, freelance rates and HR costs. - [Salary to Hourly Converter](https://mathva.com/salary-career/salary-to-hourly-converter.md): Convert an annual salary to an hourly wage, plus daily, weekly, biweekly and monthly pay. - [Cost of Living Comparison between Cities](https://mathva.com/salary-career/cost-of-living-comparison-between-cities.md): Cost of living comparison calculator: compare two U.S. cities and see the salary you’d need to keep your lifestyle, with housing, groceries and transport differences. - [Hourly to Annual Salary Converter](https://mathva.com/salary-career/hourly-to-annual-salary-converter.md): Convert an hourly wage to annual salary, with monthly, biweekly and weekly equivalents and optional overtime. - [Overtime Pay Calculator](https://mathva.com/salary-career/overtime-pay-calculator.md): Calculate weekly pay with overtime and double time from your hourly rate and hours worked. - [Time and a Half Calculator](https://mathva.com/salary-career/time-and-a-half-calculator.md): Calculate your time-and-a-half hourly rate and pay for overtime or holiday hours. - [Salary Negotiation Counter-offer Calculator](https://mathva.com/salary-career/salary-negotiation-counter-offer-calculator.md): Work out a confident salary counter-offer from your current pay, the offer and market data. - [Raise Percentage Calculator](https://mathva.com/salary-career/raise-percentage-calculator.md): Calculate your raise percentage, the dollar increase per year, month and hour, and your real raise after inflation. - [Freelance Hourly Rate Calculator](https://mathva.com/salary-career/freelance-hourly-rate-calculator.md): Calculate the freelance hourly rate you need to hit your income goal after taxes, expenses and unbillable time. - [Contractor vs Employee Pay Comparison](https://mathva.com/salary-career/contractor-vs-employee-pay-comparison.md): Compare employee salary with contractor hourly pay by accounting for benefits, employer payroll taxes and paid time off. - [Severance Pay Calculator](https://mathva.com/salary-career/severance-pay-calculator.md): Estimate your severance package from years of service, weeks-per-year formula, unused PTO and pro-rated bonus. - [PTO Accrual Calculator](https://mathva.com/salary-career/pto-accrual-calculator.md): Calculate PTO accrual per pay period and project your paid time off balance for upcoming pay periods. - [Timesheet Hours Calculator](https://mathva.com/salary-career/timesheet-hours-calculator.md): Add up timesheet hours from start and end times with breaks, and calculate regular pay, overtime and total hours. - [True Cost per Employee Calculator](https://mathva.com/salary-career/true-cost-per-employee-calculator.md): Calculate the true cost of an employee including payroll taxes, benefits, workers’ comp, equipment and overhead. - [Employee Turnover Cost Calculator](https://mathva.com/salary-career/employee-turnover-cost-calculator.md): Estimate how much employee turnover costs your business each year and the savings from improving retention. - [Sales Commission Calculator](https://mathva.com/salary-career/sales-commission-calculator.md): Calculate sales commission with base pay, quota, accelerators above quota and draws. - [Tip Pooling Calculator](https://mathva.com/salary-career/tip-pooling-calculator.md): Split a tip pool fairly among staff by hours worked or by hours weighted with role points. - [Shift Differential Calculator](https://mathva.com/salary-career/shift-differential-calculator.md): Calculate shift differential pay for night, weekend or holiday shifts as a flat amount or a percentage. - [Work Hours between Two Dates](https://mathva.com/salary-career/work-hours-between-two-dates.md): Count working days and work hours between two dates, excluding weekends and holidays. - [Freelance Break-even Client Calculator](https://mathva.com/salary-career/freelance-break-even-client-calculator.md): Work out how many clients or projects a freelancer needs each month to break even and hit an income goal. - [Remote Work Savings Calculator](https://mathva.com/salary-career/remote-work-savings-calculator.md): Calculate how much money and time you save by working remotely: fuel, parking, food, vehicle wear and commuting hours. - [Gratuity Calculator](https://mathva.com/salary-career/gratuity-calculator.md): Gratuity calculator India: calculate gratuity from last drawn basic + DA and years of service, with rounding rules, eligibility and ₹20 lakh tax exemption. ## Real Estate Investing Rental ROI, cap rate, cash flow, BRRRR, flips and landlord math. - [Rental Property ROI Calculator](https://mathva.com/real-estate/rental-property-roi-calculator.md): Analyse a rental property’s total return: cash flow, cash-on-cash, cap rate, principal paydown and appreciation. - [Cap Rate Calculator](https://mathva.com/real-estate/cap-rate-calculator.md): Calculate the capitalization (cap) rate and net operating income of an investment property, and value it at a target cap rate. - [Cash-on-cash Return Calculator](https://mathva.com/real-estate/cash-on-cash-return-calculator.md): Calculate cash-on-cash return for a rental property from cash invested and annual pre-tax cash flow. - [1% Rule Checker](https://mathva.com/real-estate/1-percent-rule-checker.md): Check whether a rental passes the 1% rule and estimate cash flow with the 50% rule. - [BRRRR Strategy Calculator](https://mathva.com/real-estate/brrrr-strategy-calculator.md): Analyse a BRRRR deal (buy, rehab, rent, refinance, repeat): cash left in, refinance proceeds, cash flow and return. - [Airbnb Income Estimator](https://mathva.com/real-estate/airbnb-income-estimator.md): Estimate Airbnb or short-term rental income from nightly rate, occupancy, cleaning fees, platform fees and costs. - [Property Management Fee Calculator](https://mathva.com/real-estate/property-management-fee-calculator.md): Calculate the true annual cost of a property manager including monthly, leasing, renewal and maintenance markup fees. - [Vacancy Rate Impact Calculator](https://mathva.com/real-estate/vacancy-rate-impact-calculator.md): See how vacancy days reduce rental income and cash flow, and find your break-even occupancy. - [Rent Increase Calculator](https://mathva.com/real-estate/rent-increase-calculator.md): Calculate a rent increase in dollars and percent, with an optional legal cap, for landlords and tenants. - [Roommate Rent Split Calculator](https://mathva.com/real-estate/roommate-rent-split-calculator.md): Split rent fairly between roommates equally, by bedroom size (with shared space) or by income. - [Security Deposit Interest Calculator](https://mathva.com/real-estate/security-deposit-interest-calculator.md): Calculate interest owed on a tenant’s security deposit where state or city law requires it. - [House Flip Profit Calculator](https://mathva.com/real-estate/house-flip-profit-calculator.md): Calculate house flip profit and ROI including rehab, holding, financing, buying and selling costs, plus the 70% rule. - [ARV (After Repair Value) Calculator](https://mathva.com/real-estate/arv-calculator.md): Estimate after-repair value (ARV) from comparable sales using price per square foot, plus the 70% rule offer. - [Real Estate Commission Calculator](https://mathva.com/real-estate/real-estate-commission-calculator.md): Calculate real estate commission, the listing and buyer-side split, the agent’s take-home and the seller’s net. - [1031 Exchange Calculator](https://mathva.com/real-estate/1031-exchange-calculator.md): Estimate the capital gains and depreciation recapture tax a 1031 exchange defers, and the replacement property you need. - [Rental Depreciation Schedule](https://mathva.com/real-estate/rental-depreciation-schedule.md): Generate a residential rental property depreciation schedule using 27.5-year MACRS straight-line and the mid-month convention. - [Landlord Cash Flow Calculator](https://mathva.com/real-estate/landlord-cash-flow-calculator.md): Calculate a landlord’s monthly cash flow after vacancy, taxes, insurance, management, maintenance, reserves and mortgage. - [Rent Affordability 30% Rule Calculator](https://mathva.com/real-estate/rent-affordability-30-percent-rule-calculator.md): Find out how much rent you can afford with the 30% rule, the landlord 40× income rule and your debts. - [Moving Cost Estimator](https://mathva.com/real-estate/moving-cost-estimator.md): Estimate moving costs for a DIY truck, moving container or full-service movers based on distance and home size. - [Home Appreciation Calculator](https://mathva.com/real-estate/home-appreciation-calculator.md): Project future home value from an appreciation rate, or calculate the annual appreciation rate between two prices. ## Business & Startup Margins, break-even, SaaS metrics, valuation, cap tables and inventory. - [Break-even Point Calculator](https://mathva.com/business/break-even-point-calculator.md): Calculate your break-even point in units and revenue from fixed costs, price and variable cost per unit. - [Profit Margin Calculator](https://mathva.com/business/profit-margin-calculator.md): Calculate gross, operating and net profit margin from revenue, cost of goods sold, operating expenses and tax. - [Markup vs Margin Converter](https://mathva.com/business/markup-vs-margin-converter.md): Convert between markup and margin and find the selling price from cost and your target markup or margin. - [Gross Profit Calculator](https://mathva.com/business/gross-profit-calculator.md): Calculate gross profit and gross margin, with cost of goods sold from beginning inventory, purchases and ending inventory. - [Burn Rate and Runway Calculator](https://mathva.com/business/burn-rate-and-runway-calculator.md): Calculate startup burn rate and cash runway, including revenue growth, and see whether you are default alive. - [Startup Equity Dilution Calculator](https://mathva.com/business/startup-equity-dilution-calculator.md): Calculate founder dilution from a funding round, including the effect of creating an option pool pre-money. - [Cap Table Simulator](https://mathva.com/business/cap-table-simulator.md): Simulate a startup cap table through seed and Series A rounds, with share prices, option pool top-ups and ownership. - [SAFE Note Conversion Calculator](https://mathva.com/business/safe-note-conversion-calculator.md): Calculate how a SAFE note converts in a priced round using the valuation cap and discount, and the resulting ownership. - [Startup Valuation Calculator](https://mathva.com/business/startup-valuation-calculator.md): Estimate a startup’s valuation with the revenue-multiple method and the venture capital (VC) method. - [Discounted Cash Flow (DCF) Calculator](https://mathva.com/business/discounted-cash-flow-calculator.md): Value a business with a discounted cash flow (DCF) model: five years of free cash flow plus a Gordon-growth terminal value. - [Customer Acquisition Cost Calculator](https://mathva.com/business/customer-acquisition-cost-calculator.md): Calculate customer acquisition cost (CAC) from marketing and sales spend, plus the CAC payback period. - [LTV:CAC Ratio Calculator](https://mathva.com/business/ltv-cac-ratio-calculator.md): Calculate customer lifetime value (LTV) and the LTV:CAC ratio for SaaS and subscription businesses. - [Churn Rate Calculator](https://mathva.com/business/churn-rate-calculator.md): Calculate customer churn rate, annualized churn, retention, customer lifetime and net revenue retention. - [MRR / ARR Calculator](https://mathva.com/business/mrr-arr-calculator.md): Calculate MRR and ARR with new, expansion, churned and contraction MRR, plus growth rate and SaaS quick ratio. - [Payback Period Calculator](https://mathva.com/business/payback-period-calculator.md): Calculate simple and discounted payback periods for an investment from its upfront cost and annual cash flows. - [Inventory Turnover Calculator](https://mathva.com/business/inventory-turnover-calculator.md): Calculate inventory turnover ratio and days sales of inventory (DSI) from COGS and average inventory. - [Reorder Point Calculator](https://mathva.com/business/reorder-point-calculator.md): Calculate the reorder point and safety stock for inventory from daily demand, lead time and service level. - [Economic Order Quantity Calculator](https://mathva.com/business/economic-order-quantity-calculator.md): Calculate the economic order quantity (EOQ) that minimises total ordering and inventory holding costs. - [Working Capital Calculator](https://mathva.com/business/working-capital-calculator.md): Calculate working capital, current ratio, quick ratio and cash ratio from your balance sheet. - [Invoice Generator with Tax](https://mathva.com/business/invoice-generator-with-tax.md): Create a simple invoice with line items, discount, sales tax and shipping — then print, save as PDF or copy it. - [Purchase Order Number Generator](https://mathva.com/business/purchase-order-number-generator.md): Generate sequential purchase order numbers with your prefix, date or department code — ready to copy into a spreadsheet. - [Business Loan Calculator](https://mathva.com/business/business-loan-calculator.md): Calculate business loan payments (monthly, biweekly or weekly), total interest and APR including fees. - [Equipment Lease vs Buy Calculator](https://mathva.com/business/equipment-lease-vs-buy-calculator.md): Compare leasing versus buying business equipment after tax deductions, financing costs and resale value. - [Employer Payroll Tax Cost Calculator](https://mathva.com/business/employer-payroll-tax-cost-calculator.md): Calculate employer payroll taxes: Social Security, Medicare, FUTA and state unemployment tax per employee and in total. - [Partnership Profit Split Calculator](https://mathva.com/business/partnership-profit-split-calculator.md): Split partnership or LLC profits by capital, hours, equal shares or custom percentages, after guaranteed payments. ## E-commerce & Selling Marketplace fees, product pricing, shipping and ad profitability. - [Amazon FBA Profit Calculator](https://mathva.com/ecommerce/amazon-fba-profit-calculator.md): Calculate Amazon FBA profit per unit and per month after referral fees, fulfillment fees, storage, ads and returns. - [Etsy Fee and Profit Calculator](https://mathva.com/ecommerce/etsy-fee-and-profit-calculator.md): Calculate Etsy fees — listing, transaction, payment processing and Offsite Ads — and your profit per sale. - [Amazon Referral Fee Calculator](https://mathva.com/ecommerce/amazon-referral-fee-calculator.md): Look up and calculate the Amazon referral fee for your category and price, including tiered categories. - [eBay Fee Calculator](https://mathva.com/ecommerce/ebay-fee-calculator.md): Calculate eBay final value fees, promoted listing costs and your profit after item and shipping costs. - [Shopify Profit Margin Calculator](https://mathva.com/ecommerce/shopify-profit-margin-calculator.md): Calculate Shopify store profit margin per order and per month after product costs, shipping, payment fees, ads and apps. - [Stripe / PayPal Fee Calculator](https://mathva.com/ecommerce/stripe-paypal-fee-calculator.md): Calculate Stripe, PayPal and Square processing fees, what you receive, or how much to charge to net a specific amount. - [Dropshipping Profit Calculator](https://mathva.com/ecommerce/dropshipping-profit-calculator.md): Calculate dropshipping profit per order, margin, break-even ad cost (CPA) and break-even ROAS. - [Print-on-demand Profit Calculator](https://mathva.com/ecommerce/print-on-demand-profit-calculator.md): Calculate print-on-demand profit per sale after base cost, shipping, marketplace fees and ads. - [Wholesale Pricing Calculator](https://mathva.com/ecommerce/wholesale-pricing-calculator.md): Set wholesale and suggested retail prices from your unit cost, target margin and retailer markup. - [Retail Price Calculator with Target Margin](https://mathva.com/ecommerce/retail-price-calculator-with-target-margin.md): Find the retail price that achieves your target profit margin from unit cost, with optional .99 charm pricing. - [Discount and Sale Price Calculator](https://mathva.com/ecommerce/discount-and-sale-price-calculator.md): Calculate the sale price after one or two stacked percentage discounts, total savings and price with tax. - [Bulk Order Discount Calculator](https://mathva.com/ecommerce/bulk-order-discount-calculator.md): Calculate bulk order pricing with quantity discount tiers and see how much more you’d save at the next tier. - [Shipping Cost by Weight and Zone Estimator](https://mathva.com/ecommerce/shipping-cost-by-weight-and-zone-estimator.md): Shipping cost calculator by weight and zone: compare estimated USPS, UPS and FedEx prices with dimensional weight, distance-based zones and commercial discounts. - [Dimensional Weight Calculator](https://mathva.com/ecommerce/dimensional-weight-calculator.md): Calculate dimensional (DIM) weight and billable shipping weight for UPS, FedEx and USPS packages. - [Customs Duty and Import Tax Estimator](https://mathva.com/ecommerce/customs-duty-and-import-tax-estimator.md): Estimate customs duty, tariffs, import VAT/GST and total landed cost for imported goods. - [Product Bundle Pricing Calculator](https://mathva.com/ecommerce/product-bundle-pricing-calculator.md): Price a product bundle: bundle price, customer savings, margin and the sales lift needed to justify the discount. - [Coupon Stacking Calculator](https://mathva.com/ecommerce/coupon-stacking-calculator.md): Stack multiple percentage and dollar-off coupons, and find the order that gives the lowest final price. - [Return Rate Impact Calculator](https://mathva.com/ecommerce/return-rate-impact-calculator.md): Calculate how product returns reduce revenue and profit, including return shipping, processing and unsellable stock. - [ROAS Calculator](https://mathva.com/ecommerce/roas-calculator.md): Calculate return on ad spend (ROAS), ACoS and profit after advertising from revenue, ad spend and margin. - [Break-even ROAS Calculator](https://mathva.com/ecommerce/break-even-roas-calculator.md): Find your break-even ROAS and maximum cost per acquisition from price, product cost, shipping and fees. ## Crypto Crypto profit, DCA, staking, mining, DeFi and leverage math. - [Crypto Profit/loss Calculator](https://mathva.com/crypto/crypto-profit-loss-calculator.md): Calculate cryptocurrency profit or loss, ROI and break-even price including exchange buy and sell fees. - [Crypto DCA Calculator](https://mathva.com/crypto/crypto-dca-calculator.md): Calculate the results of dollar-cost averaging into crypto: average cost, coins accumulated, value and ROI. - [Staking Rewards Calculator](https://mathva.com/crypto/staking-rewards-calculator.md): Estimate crypto staking rewards in coins and dollars after validator commission, with or without compounding. - [Mining Profitability Calculator](https://mathva.com/crypto/mining-profitability-calculator.md): Estimate Bitcoin mining profitability from hashrate, power use, electricity cost, network hashrate and BTC price. - [Gas Fee Estimator](https://mathva.com/crypto/gas-fee-estimator.md): Estimate Ethereum gas fees in ETH and dollars for transfers, swaps and mints from gas units, gwei and ETH price. - [Impermanent Loss Calculator](https://mathva.com/crypto/impermanent-loss-calculator.md): Calculate impermanent loss for a 50/50 liquidity pool and compare the LP position with simply holding both tokens. - [Crypto Portfolio Allocation Tool](https://mathva.com/crypto/crypto-portfolio-allocation-tool.md): Plan a crypto portfolio allocation by percentage and see how much to buy or sell of each asset to rebalance. - [Bitcoin Halving Countdown](https://mathva.com/crypto/bitcoin-halving-countdown.md): Count down to the next Bitcoin halving: estimated date, blocks remaining and the new block reward. - [Satoshi to USD Converter](https://mathva.com/crypto/satoshi-to-usd-converter.md): Convert satoshis to USD, USD to sats, or BTC to satoshis at any Bitcoin price. - [Crypto Tax Lot Calculator](https://mathva.com/crypto/crypto-tax-lot-calculator.md): Calculate crypto capital gains by tax lot using FIFO, LIFO or HIFO, split into short- and long-term gains. - [Leverage Liquidation Price Calculator](https://mathva.com/crypto/leverage-liquidation-price-calculator.md): Calculate the liquidation price for leveraged long or short crypto futures positions, plus position size and P/L. - [APY vs APR Converter](https://mathva.com/crypto/apy-vs-apr-converter.md): Convert between APR and APY for any compounding frequency — useful for DeFi, staking and savings yields. - [Yield Farming Calculator](https://mathva.com/crypto/yield-farming-calculator.md): Estimate yield farming returns after compounding, gas costs and reward-token price changes. - [Airdrop Value Tracker](https://mathva.com/crypto/airdrop-value-tracker.md): Calculate the value of a crypto airdrop, the unlocked portion and the income tax you may owe. - [Crypto to Fiat Converter with Fees](https://mathva.com/crypto/crypto-to-fiat-converter-with-fees.md): Convert crypto to dollars and see exactly what you receive after trading fees, spread and withdrawal fees. ## Health & Fitness BMI, body fat, calories, macros, running pace, heart rate and strength. - [BMI Calculator](https://mathva.com/health-fitness/bmi-calculator.md): Calculate your body mass index (BMI) from height and weight, see your weight category and the healthy weight range for your height. - [Body Fat Percentage Calculator](https://mathva.com/health-fitness/body-fat-percentage-calculator.md): Estimate body fat percentage with the U.S. Navy tape-measure method, plus fat mass, lean mass and your ACE fitness category. - [TDEE Calculator](https://mathva.com/health-fitness/tdee-calculator.md): Estimate your TDEE — total calories burned per day — from BMR and activity level, with calorie targets to maintain, lose or gain weight. - [Macro Calculator](https://mathva.com/health-fitness/macro-calculator.md): Calculate daily macros — protein, carbs and fat in grams — for fat loss, maintenance or muscle gain with balanced, high-protein, low-carb or keto splits. - [Ideal Weight Calculator](https://mathva.com/health-fitness/ideal-weight-calculator.md): Find your ideal body weight by height and sex with the Devine, Robinson, Miller and Hamwi formulas plus the healthy BMI weight range. - [One Rep Max Calculator](https://mathva.com/health-fitness/one-rep-max-calculator.md): Estimate your one-rep max (1RM) from any set of reps with seven proven formulas, plus a percentage chart for programming your training weights. - [Running Pace Calculator](https://mathva.com/health-fitness/running-pace-calculator.md): Calculate running pace per mile or km, finish time or distance, plus speed and equivalent finish times for 5K, 10K, half and full marathon. - [Heart Rate Zone Calculator](https://mathva.com/health-fitness/heart-rate-zone-calculator.md): Calculate your five heart rate training zones with the Karvonen (heart rate reserve) or percent-of-max method, using your age and resting heart rate. - [Calories Burned by Activity](https://mathva.com/health-fitness/calories-burned-by-activity.md): Calculate calories burned for 40+ activities — running, cycling, swimming, lifting, sports and chores — from your weight and workout time. - [BMR Calculator](https://mathva.com/health-fitness/bmr-calculator.md): Calculate your basal metabolic rate (BMR) — calories burned at rest — with the Mifflin–St Jeor, Harris–Benedict and Katch–McArdle equations. - [Calorie Deficit Calculator](https://mathva.com/health-fitness/calorie-deficit-calculator.md): Find the calorie deficit and daily calorie intake needed to lose weight at your chosen rate, and how many weeks it will take to reach your goal. - [Weight Loss Timeline Calculator](https://mathva.com/health-fitness/weight-loss-timeline-calculator.md): Project your weight week by week and the date you’ll reach your goal weight, with a dynamic model that adjusts calorie burn as you lose weight. - [Waist-to-hip Ratio Calculator](https://mathva.com/health-fitness/waist-to-hip-ratio-calculator.md): Calculate your waist-to-hip ratio and see your cardiovascular health risk and body shape using World Health Organization cut-offs. - [Lean Body Mass Calculator](https://mathva.com/health-fitness/lean-body-mass-calculator.md): Estimate lean body mass (LBM) — weight minus body fat — with the Boer, James and Hume formulas or your known body fat percentage. - [Protein Intake Calculator](https://mathva.com/health-fitness/protein-intake-calculator.md): Calculate how much protein you need per day and per meal based on body weight and goals — from sedentary to muscle building, fat loss and aging. - [Daily Water Intake Calculator](https://mathva.com/health-fitness/daily-water-intake-calculator.md): Calculate how much water to drink each day based on sex, weight, exercise, climate and pregnancy, in liters, cups and ounces. - [Wilks / DOTS Score Calculator](https://mathva.com/health-fitness/wilks-dots-score-calculator.md): Calculate Wilks, Wilks 2020, DOTS and IPF GL points to compare powerlifting totals across body weights and sexes. - [Marathon Time Predictor](https://mathva.com/health-fitness/marathon-time-predictor.md): Predict your marathon, half marathon, 10K and 5K times from a recent race using Riegel’s endurance formula, with target paces. - [Race Split Calculator](https://mathva.com/health-fitness/race-split-calculator.md): Get even or negative race splits for any goal time — per kilometer or mile — for a 5K, 10K, half marathon or marathon. - [VO2 Max Estimator](https://mathva.com/health-fitness/vo2-max-estimator.md): Estimate VO₂ max from a race time, Cooper 12-minute run, Rockport walk test or resting heart rate, and see how your fitness compares for your age. - [Max Heart Rate Calculator](https://mathva.com/health-fitness/max-heart-rate-calculator.md): Estimate your maximum heart rate by age with the Tanaka, Fox (220 − age), Gellish, Nes and Gulati formulas, and see target heart rates by intensity. - [Steps to Calories Converter](https://mathva.com/health-fitness/steps-to-calories-converter.md): Convert steps to calories burned based on your weight, height and walking pace, plus distance and walking time. - [Steps to Miles Converter](https://mathva.com/health-fitness/steps-to-miles-converter.md): Convert steps to miles and kilometers using your height or measured stride length, for walking or running. - [Swimming Pace Calculator](https://mathva.com/health-fitness/swimming-pace-calculator.md): Calculate swim pace per 100 meters or yards, convert between pool units, predict triathlon swim times and find your critical swim speed (CSS). - [Cycling Power Calculator](https://mathva.com/health-fitness/cycling-power-calculator.md): Estimate cycling power in watts for any speed, weight, grade, riding position and wind — with the split between aero drag, rolling resistance and climbing. - [FTP Calculator](https://mathva.com/health-fitness/ftp-calculator.md): Calculate cycling FTP from a 20-minute, 8-minute, ramp or 60-minute test, with watts per kilogram and Coggan power training zones. - [Sleep Cycle / Bedtime Calculator](https://mathva.com/health-fitness/sleep-cycle-bedtime-calculator.md): Find the best time to go to bed or wake up based on 90-minute sleep cycles, so you wake between cycles feeling less groggy. - [Blood Alcohol Content Calculator](https://mathva.com/health-fitness/blood-alcohol-content-calculator.md): Estimate blood alcohol content (BAC) from drinks, body weight, sex and time using the Widmark formula, plus hours until sober. - [Caffeine Half-life Calculator](https://mathva.com/health-fitness/caffeine-half-life-calculator.md): See how much caffeine is still in your body at bedtime from coffee, tea and energy drinks, using caffeine’s half-life, with a chart across the day. - [Standard Drinks Calculator](https://mathva.com/health-fitness/standard-drinks-calculator.md): Convert any beer, wine, cocktail or spirit into US standard drinks, UK units and grams of alcohol from serving size and ABV. - [Body Surface Area Calculator](https://mathva.com/health-fitness/body-surface-area-calculator.md): Calculate body surface area (BSA) in square meters with the Mosteller, Du Bois, Haycock, Gehan-George, Boyd and Fujimoto formulas. - [Waist Circumference Risk Checker](https://mathva.com/health-fitness/waist-circumference-risk-checker.md): Check your waist circumference health risk using NIH and IDF thresholds, waist-to-height ratio and the combined BMI-plus-waist risk table. - [Strength Standards Percentile Calculator](https://mathva.com/health-fitness/strength-standards-percentile-calculator.md): Compare your squat, bench, deadlift and overhead press to strength standards and see your level and estimated percentile for your sex and body weight. - [Push-up and Pull-up Percentile Calculator](https://mathva.com/health-fitness/push-up-and-pull-up-percentile-calculator.md): See how your push-up and pull-up counts compare by age and sex, with fitness test ratings and estimated percentiles. - [Bench Press Standards Calculator](https://mathva.com/health-fitness/bench-press-standards-calculator.md): Find out how strong your bench press is for your body weight and sex, with beginner to elite standards by weight class. ## Medical, Pregnancy & Pets Due dates, ovulation, baby growth, lab conversions and pet age and dosing. - [Pregnancy Due Date Calculator](https://mathva.com/medical-pregnancy-pets/pregnancy-due-date-calculator.md): Calculate your pregnancy due date from your last period, conception, IVF transfer or ultrasound, plus how far along you are and key milestones. - [Ovulation Calculator](https://mathva.com/medical-pregnancy-pets/ovulation-calculator.md): Estimate your ovulation date and fertile window for the next six cycles from your last period and cycle length. - [Dog Age in Human Years](https://mathva.com/medical-pregnancy-pets/dog-age-in-human-years.md): Convert your dog’s age to human years by size, with life stage and a comparison to the new DNA-methylation “epigenetic clock” formula. - [Conception Date Calculator](https://mathva.com/medical-pregnancy-pets/conception-date-calculator.md): Estimate the date of conception from a due date, last menstrual period or birth date, including the likely window when it happened. - [Pregnancy Weight Gain Tracker](https://mathva.com/medical-pregnancy-pets/pregnancy-weight-gain-tracker.md): Track pregnancy weight gain week by week against Institute of Medicine guidelines for your pre-pregnancy BMI, including twins. - [Baby Growth Percentile Calculator](https://mathva.com/medical-pregnancy-pets/baby-growth-percentile-calculator.md): Find your baby’s weight, length and head circumference percentiles using WHO growth standards for boys and girls from birth to 24 months. - [Baby Feeding Amount Calculator](https://mathva.com/medical-pregnancy-pets/baby-feeding-amount-calculator.md): Calculate how much formula or breast milk your baby needs per day and per feeding by age and weight, in ounces and milliliters. - [Formula Mixing Calculator](https://mathva.com/medical-pregnancy-pets/formula-mixing-calculator.md): Work out how many scoops of formula powder, concentrate or water to use for any bottle size, with batch amounts and calories. - [Diaper Usage Estimator](https://mathva.com/medical-pregnancy-pets/diaper-usage-estimator.md): Estimate how many diapers your baby will use by size until potty training, and the total cost of disposables versus cloth. - [Child Adult Height Predictor](https://mathva.com/medical-pregnancy-pets/child-adult-height-predictor.md): Predict your child’s adult height from both parents’ heights using the mid-parental method, with a likely range and an early-height estimate. - [Vaccination Schedule Generator](https://mathva.com/medical-pregnancy-pets/vaccination-schedule-generator.md): Generate a personalized childhood vaccination schedule with dates from birth to 16 years, based on the standard routine U.S. schedule. - [Pediatric Dose by Weight Calculator](https://mathva.com/medical-pregnancy-pets/pediatric-dose-by-weight-calculator.md): Check weight-based children’s acetaminophen (Tylenol) and ibuprofen (Motrin, Advil) doses in mL or tablets, with timing and daily maximums. - [Menstrual Cycle Calculator](https://mathva.com/medical-pregnancy-pets/menstrual-cycle-calculator.md): Predict your next six periods, fertile windows and PMS days from your last period, cycle length and period length. - [Menopause Age Estimator](https://mathva.com/medical-pregnancy-pets/menopause-age-estimator.md): Estimate when you might reach natural menopause from your mother’s menopause age, smoking, pregnancies, first period and BMI. - [IVF Due Date Calculator](https://mathva.com/medical-pregnancy-pets/ivf-due-date-calculator.md): Calculate your IVF due date from a day-3, day-5 or day-6 embryo transfer or egg retrieval date, plus gestational age and milestones. - [Breast Milk Storage Timer](https://mathva.com/medical-pregnancy-pets/breast-milk-storage-timer.md): Live countdown showing how long expressed breast milk stays safe at room temperature, in the fridge, freezer or cooler, using CDC guidelines. - [eGFR Calculator](https://mathva.com/medical-pregnancy-pets/egfr-calculator.md): Calculate estimated glomerular filtration rate (eGFR) with the race-free CKD-EPI 2021 creatinine equation, optional cystatin C, and CKD stage. - [A1c to Average Glucose Converter](https://mathva.com/medical-pregnancy-pets/a1c-to-average-glucose-converter.md): Convert HbA1c to estimated average glucose (eAG) in mg/dL and mmol/L, glucose to A1c, and CGM average to GMI, with ADA categories. - [Insulin Dose Calculator](https://mathva.com/medical-pregnancy-pets/insulin-dose-calculator.md): Estimate a mealtime insulin bolus from carbs, insulin-to-carb ratio, correction factor and insulin on board — for people trained by their care team. - [Blood Pressure Category Checker](https://mathva.com/medical-pregnancy-pets/blood-pressure-category-checker.md): Check your blood pressure category — normal, elevated, stage 1 or 2 hypertension — from one or several readings using American Heart Association guidelines. - [Cholesterol Ratio Calculator](https://mathva.com/medical-pregnancy-pets/cholesterol-ratio-calculator.md): Calculate cholesterol ratios — total/HDL, LDL/HDL, triglyceride/HDL — plus non-HDL and calculated LDL from your lipid panel in mg/dL or mmol/L. - [Lab Unit Converter (mg/dL to mmol/L)](https://mathva.com/medical-pregnancy-pets/lab-unit-converter.md): Convert lab results between US conventional and SI units — glucose, cholesterol, creatinine, vitamin D, B12, hemoglobin and more. - [Cat Age in Human Years](https://mathva.com/medical-pregnancy-pets/cat-age-in-human-years.md): Convert your cat’s age into human years and see its life stage, life expectancy and recommended vet visit frequency. - [Dog Food Portion Calculator](https://mathva.com/medical-pregnancy-pets/dog-food-portion-calculator.md): Calculate how much to feed your dog per day in cups and calories from weight, life stage, activity and your food’s calorie density. - [Pet Medication Dose by Weight](https://mathva.com/medical-pregnancy-pets/pet-medication-dose-by-weight.md): Check a vet-prescribed pet medication dose by weight — convert mg/kg or mg/lb into tablets or mL for dogs and cats. ## Cooking & Kitchen Recipe scaling, cup-to-gram conversions, baking math, roasting times and coffee ratios. - [Recipe Serving Scaler](https://mathva.com/cooking/recipe-serving-scaler.md): Scale any recipe up or down to the number of servings you need — fractions, ranges and teaspoon-to-cup conversions handled automatically. - [Cups to Grams Converter by Ingredient](https://mathva.com/cooking/cups-to-grams-converter-by-ingredient.md): Convert cups, tablespoons and teaspoons to grams (and back) for flour, sugar, butter, oats, honey and 30+ baking ingredients. - [Oven Temperature Converter](https://mathva.com/cooking/oven-temperature-converter.md): Convert oven temperatures between Fahrenheit, Celsius and gas mark, with fan/convection oven adjustments and a full conversion chart. - [Baking Pan Size Converter](https://mathva.com/cooking/baking-pan-size-converter.md): Convert a recipe between baking pan sizes — round, square, 9×13, sheet, loaf, Bundt and muffin — and see how much to scale ingredients. - [Butter Stick Converter](https://mathva.com/cooking/butter-stick-converter.md): Convert butter between US sticks, cups, tablespoons, teaspoons, grams, ounces and European 250 g blocks. - [Sourdough Starter Calculator](https://mathva.com/cooking/sourdough-starter-calculator.md): Calculate how much starter, flour and water to use when feeding sourdough at any ratio (1:1:1, 1:2:2, 1:5:5), with hydration and peak timing. - [Baker's Percentage Calculator](https://mathva.com/cooking/bakers-percentage-calculator.md): Convert a bread recipe to baker’s percentages, or turn percentages into grams for any flour weight, with total dough weight and hydration. - [Dough Hydration Calculator](https://mathva.com/cooking/dough-hydration-calculator.md): Calculate true dough hydration including water from milk, eggs, butter and sourdough starter, and the water needed to hit a target hydration. - [Turkey Cooking Time Calculator](https://mathva.com/cooking/turkey-cooking-time-calculator.md): Find how long to roast a turkey by weight — stuffed or unstuffed — when to put it in the oven, and how long to thaw it. - [Roast Cooking Time by Weight](https://mathva.com/cooking/roast-cooking-time-by-weight.md): Estimate roasting time by weight for beef, pork, ham, lamb and chicken, with oven temperature, pull temperature and USDA safe temperatures. - [Sous Vide Time and Temp Chart](https://mathva.com/cooking/sous-vide-time-and-temp-chart.md): Sous vide time and temperature chart for steak, chicken, pork, salmon, eggs and vegetables, with times adjusted for thickness. - [Air Fryer Conversion Calculator](https://mathva.com/cooking/air-fryer-conversion-calculator.md): Convert oven recipes to air fryer temperature and time, with when to check, shake and flip for fries, chicken, vegetables and baked goods. - [Slow Cooker to Instant Pot Converter](https://mathva.com/cooking/slow-cooker-to-instant-pot-converter.md): Convert slow cooker recipes to Instant Pot pressure cooking times, including release method, liquid and total time saved. - [Brine Calculator](https://mathva.com/cooking/brine-calculator.md): Calculate salt and sugar for a wet brine by water volume and strength, with tablespoon amounts for table, Morton and Diamond Crystal kosher salt. - [Meat per Person Party Calculator](https://mathva.com/cooking/meat-per-person-party-calculator.md): Work out how much meat to buy per person for a party or BBQ — pulled pork, brisket, burgers, wings, ribs and more — including cooking loss. - [Pizza Dough Calculator](https://mathva.com/cooking/pizza-dough-calculator.md): Calculate pizza dough ingredients in grams for any number of pizzas — Neapolitan, New York, Detroit or custom hydration, salt and yeast. - [Coffee to Water Ratio Calculator](https://mathva.com/cooking/coffee-to-water-ratio-calculator.md): Get the perfect coffee-to-water ratio for drip, pour-over, French press, AeroPress, Chemex, cold brew and moka pot in grams and tablespoons. - [Espresso Ratio Calculator](https://mathva.com/cooking/espresso-ratio-calculator.md): Calculate espresso yield from dose and brew ratio (ristretto, normale, lungo), diagnose shot time, and find extraction yield from TDS. - [Cocktail Dilution Calculator](https://mathva.com/cooking/cocktail-dilution-calculator.md): Calculate cocktail dilution, final ABV and volume for stirred, shaken or built drinks — and how much water to add when batching. - [Homebrew ABV Calculator](https://mathva.com/cooking/homebrew-abv-calculator.md): Calculate homebrew beer ABV from original and final gravity, plus attenuation, degrees Plato and calories per 12 oz. - [IBU Calculator](https://mathva.com/cooking/ibu-calculator.md): Calculate beer bitterness (IBU) with the Tinseth formula from hop additions, alpha acids, boil times, batch size and gravity. - [Ice Cream Base Calculator](https://mathva.com/cooking/ice-cream-base-calculator.md): Balance an ice cream base: calculate cream, milk, sugar, yolks and milk powder for your target butterfat, with total solids. - [Canning Processing Time Calculator](https://mathva.com/cooking/canning-processing-time-calculator.md): Find safe home canning processing times for water bath and pressure canning, adjusted for jar size, altitude and gauge type (USDA/NCHFP). - [Food Cost per Serving Calculator](https://mathva.com/cooking/food-cost-per-serving-calculator.md): Calculate recipe cost and cost per serving from ingredient package prices, plus a menu price at your target food cost percentage. - [Meal Prep Macro Splitter](https://mathva.com/cooking/meal-prep-macro-splitter.md): Split daily macros across meals for meal prep, and work out how many grams of a batch recipe to put in each container. ## Home, DIY & Construction Paint, flooring, concrete, lumber, roofing, decks, pools and gardens. - [Paint Quantity Calculator](https://mathva.com/home-diy/paint-quantity-calculator.md): Calculate how many gallons of paint you need for a room’s walls and ceiling, minus doors and windows. - [Tile Calculator with Waste Factor](https://mathva.com/home-diy/tile-calculator-with-waste-factor.md): Calculate how many tiles and boxes you need for a floor or wall, including grout joints and waste. - [Concrete Volume Calculator](https://mathva.com/home-diy/concrete-volume-calculator.md): Calculate concrete volume in cubic yards and bags for slabs, patios, footings and round columns. - [Wallpaper Roll Calculator](https://mathva.com/home-diy/wallpaper-roll-calculator.md): Calculate how many wallpaper rolls you need using the strip method with pattern repeat and waste allowance. - [Flooring Square Footage Calculator](https://mathva.com/home-diy/flooring-square-footage-calculator.md): Calculate flooring square footage for multiple rooms, boxes to buy with waste allowance, and total cost. - [Grout Calculator](https://mathva.com/home-diy/grout-calculator.md): Calculate how much grout you need from tile size, thickness, joint width and area. - [Carpet Cost Calculator](https://mathva.com/home-diy/carpet-cost-calculator.md): Estimate carpet yardage from a 12 or 15 ft roll, plus pad and installation cost for a room. - [Rebar Spacing Calculator](https://mathva.com/home-diy/rebar-spacing-calculator.md): Calculate rebar quantity for a concrete slab grid: number of bars, linear feet, weight and stock lengths with laps. - [Gravel and Mulch Calculator](https://mathva.com/home-diy/gravel-and-mulch-calculator.md): Calculate cubic yards, tons and bags of gravel, mulch, topsoil or sand for any area and depth. - [Drywall Sheet Calculator](https://mathva.com/home-diy/drywall-sheet-calculator.md): Calculate how many drywall sheets, screws, joint compound and tape you need for a room. - [Stud Spacing / Framing Calculator](https://mathva.com/home-diy/stud-spacing-framing-calculator.md): Calculate how many wall studs and plates you need for framing, including corners and openings. - [Roof Pitch Calculator](https://mathva.com/home-diy/roof-pitch-calculator.md): Calculate roof pitch, angle, slope percentage and the multiplier to convert footprint area to actual roof area. - [Roofing Shingle Bundle Calculator](https://mathva.com/home-diy/roofing-shingle-bundle-calculator.md): Calculate roofing squares, shingle bundles, underlayment, starter strip and ridge cap for a gable roof. - [Gutter Size Calculator](https://mathva.com/home-diy/gutter-size-calculator.md): Size gutters and downspouts from roof drainage area, pitch and local maximum rainfall intensity. - [Deck Board and Joist Calculator](https://mathva.com/home-diy/deck-board-and-joist-calculator.md): Calculate deck boards, joists, rim joists and screws for a rectangular deck. - [Fence Post and Panel Calculator](https://mathva.com/home-diy/fence-post-and-panel-calculator.md): Calculate fence panels, posts and concrete for a fence line with gates. - [Stair Rise and Run Calculator](https://mathva.com/home-diy/stair-rise-and-run-calculator.md): Calculate stair risers, treads, total run, stringer length and angle from the total rise. - [Insulation R-value Calculator](https://mathva.com/home-diy/insulation-r-value-calculator.md): Calculate how much insulation thickness you need to reach a target R-value for attics, walls and floors. - [Board Foot Calculator](https://mathva.com/home-diy/board-foot-calculator.md): Calculate board feet and lumber cost from thickness, width, length and quantity. - [Lumber Cost Calculator](https://mathva.com/home-diy/lumber-cost-calculator.md): Build a lumber shopping list and calculate total cost, pieces and board feet with waste and sales tax. - [Brick and Block Calculator](https://mathva.com/home-diy/brick-and-block-calculator.md): Calculate how many bricks or concrete blocks you need for a wall, plus mortar bags and cost. - [Mortar Mix Calculator](https://mathva.com/home-diy/mortar-mix-calculator.md): Calculate mortar volume and the cement, lime and sand needed to lay bricks or blocks, or the number of premix bags. - [Plywood Sheet Cut Optimizer](https://mathva.com/home-diy/plywood-sheet-cut-optimizer.md): Plan plywood and sheet-goods cuts: fit your parts onto the fewest sheets with a strip cutting layout. - [Linear Cut List Optimizer](https://mathva.com/home-diy/linear-cut-list-optimizer.md): Optimize a linear cut list for boards, pipe or trim: fewest stock lengths, least waste, with a cutting plan. - [Miter Angle Calculator](https://mathva.com/home-diy/miter-angle-calculator.md): Calculate miter saw angles for picture frames, polygons and corners of any angle. - [Window and Door Header Sizing](https://mathva.com/home-diy/window-and-door-header-sizing.md): Window and door header size calculator: find the right built-up lumber or LVL header for an opening based on roof, floor and snow loads, with jack stud counts. - [Beam Span Calculator](https://mathva.com/home-diy/beam-span-calculator.md): Beam span calculator for built-up lumber, LVL and glulam beams: find the maximum span and required size for floor, deck and roof loads with deflection checks. - [Pool Volume and Chemical Calculator](https://mathva.com/home-diy/pool-volume-and-chemical-calculator.md): Calculate pool volume in gallons and how much chlorine and baking soda to add to reach target levels. - [Hot Tub Chemical Dosing Calculator](https://mathva.com/home-diy/hot-tub-chemical-dosing-calculator.md): Calculate how much chlorine, bromine or non-chlorine shock to add to a hot tub to reach your target level. - [Sprinkler Coverage Calculator](https://mathva.com/home-diy/sprinkler-coverage-calculator.md): Plan sprinkler coverage: heads needed for head-to-head spacing, water flow and number of zones. - [Lawn Seed and Fertilizer Calculator](https://mathva.com/home-diy/lawn-seed-and-fertilizer-calculator.md): Calculate how much grass seed and fertilizer you need for a new lawn or overseeding, by grass type. - [Garden Bed Soil Volume Calculator](https://mathva.com/home-diy/garden-bed-soil-volume-calculator.md): Calculate how much soil you need for garden beds in cubic feet, cubic yards and bags. - [Raised Bed Planner](https://mathva.com/home-diy/raised-bed-planner.md): Plan a raised garden bed: lumber needed, soil volume and mix, and square-foot planting spaces. - [Firewood Cord Calculator](https://mathva.com/home-diy/firewood-cord-calculator.md): Calculate how many cords or face cords of firewood are in a stack and check what you should pay. - [Shed Foundation Calculator](https://mathva.com/home-diy/shed-foundation-calculator.md): Calculate materials for a shed foundation: gravel pad, concrete slab or concrete piers. ## Energy & Utilities Electricity bills, solar, HVAC sizing, appliances and electrical math. - [Electricity Bill Calculator by kWh](https://mathva.com/energy/electricity-bill-calculator-by-kwh.md): Estimate your electricity bill from kWh used, energy and delivery rates, fixed charges and taxes. - [Solar Panel Savings Calculator](https://mathva.com/energy/solar-panel-savings-calculator.md): Estimate solar panel savings, bill offset and payback for your home from system size, sun hours and electricity rates. - [Appliance Running Cost Calculator](https://mathva.com/energy/appliance-running-cost-calculator.md): Calculate how much an appliance costs to run per hour, month and year from its wattage and usage. - [Solar Payback Period Calculator](https://mathva.com/energy/solar-payback-period-calculator.md): Calculate how many years solar panels take to pay for themselves, and the lifetime return on investment. - [Battery Backup Sizing Calculator](https://mathva.com/energy/battery-backup-sizing-calculator.md): Size a home backup battery by listing essential loads, hours of use and days of backup. - [Generator Sizing Calculator](https://mathva.com/energy/generator-sizing-calculator.md): Calculate what size generator you need from running and starting watts of the appliances you want to power. - [Heat Pump vs Furnace Cost Comparison](https://mathva.com/energy/heat-pump-vs-furnace-cost-comparison.md): Compare annual heating costs of a heat pump and a gas furnace based on fuel prices and efficiency. - [HVAC BTU Sizing Calculator](https://mathva.com/energy/hvac-btu-sizing-calculator.md): Estimate the BTU and tonnage of air conditioner or heat pump you need for a room or home. - [Water Heater Running Cost Calculator](https://mathva.com/energy/water-heater-running-cost-calculator.md): Calculate how much your water heater costs to run per year and compare electric, gas, tankless and heat pump models. - [Insulation Payback Calculator](https://mathva.com/energy/insulation-payback-calculator.md): Calculate how much you save on heating by adding insulation, and the payback period on the project. - [LED vs Incandescent Savings Calculator](https://mathva.com/energy/led-vs-incandescent-savings-calculator.md): Calculate how much you save by switching from incandescent to LED bulbs, including bulb replacements and payback. - [EV Home Charging Cost Calculator](https://mathva.com/energy/ev-home-charging-cost-calculator.md): Estimate monthly EV home charging costs with time-of-use rates and charging losses, compared with gas. - [Phantom Load Calculator](https://mathva.com/energy/phantom-load-calculator.md): Calculate how much phantom (standby) power from electronics costs you per year. - [Gas vs Electric Cooking Cost](https://mathva.com/energy/gas-vs-electric-cooking-cost.md): Compare the yearly cost of cooking with a gas stove versus an electric or induction cooktop. - [Home Energy Audit Scorecard](https://mathva.com/energy/home-energy-audit-scorecard.md): Score your home’s energy efficiency in two minutes and get a prioritized list of upgrades. - [Watts to Amps Converter](https://mathva.com/energy/watts-to-amps-converter.md): Convert watts to amps or amps to watts for DC, single-phase and three-phase circuits at any voltage. - [Voltage Drop Calculator](https://mathva.com/energy/voltage-drop-calculator.md): Calculate voltage drop for copper or aluminum wire from gauge, length, current and voltage. - [Wire Gauge Calculator](https://mathva.com/energy/wire-gauge-calculator.md): Find the right wire gauge for a circuit based on current, distance, voltage and allowable voltage drop. - [Circuit Breaker Load Calculator](https://mathva.com/energy/circuit-breaker-load-calculator.md): Check whether a circuit breaker is overloaded by adding up device loads, with the 80% continuous-load rule. - [Kilowatt to Horsepower Converter](https://mathva.com/energy/kilowatt-to-horsepower-converter.md): Convert kilowatts to horsepower and horsepower to kilowatts, including metric horsepower (PS). - [Wire Size Calculator (AWG)](https://mathva.com/energy/wire-size-calculator.md): Wire size calculator (AWG): find the right copper or aluminum wire gauge from amps, distance, voltage and voltage drop, using NEC ampacity tables. ## Travel Flight times, time zones, Schengen days, currency, tipping and trip budgets. - [Flight Time Calculator between Cities](https://mathva.com/travel/flight-time-calculator-between-cities.md): Estimate nonstop flight time and distance between two cities, with local arrival time, time difference and jet-stream effects. - [Currency Converter with Card Fees](https://mathva.com/travel/currency-converter-with-card-fees.md): Convert currencies at today’s mid-market rate and see the real cost after card foreign transaction fees, ATM fees and dynamic currency conversion. - [Jet Lag Adjustment Planner](https://mathva.com/travel/jet-lag-adjustment-planner.md): Plan a jet lag schedule: shift bedtime and wake time before you fly, with light-exposure tips and expected recovery days for east or west travel. - [Time Zone Meeting Planner](https://mathva.com/travel/time-zone-meeting-planner.md): Find the best meeting time across up to four cities’ time zones, with an hour-by-hour grid showing who is inside working hours. - [Layover Feasibility Checker](https://mathva.com/travel/layover-feasibility-checker.md): Check whether your layover is long enough, based on connection type, airport size, terminal change, customs, security and baggage recheck. - [Airline Baggage Fee Comparison](https://mathva.com/travel/airline-baggage-fee-comparison.md): Compare checked bag and carry-on fees across major U.S. airlines for your trip and see the true total cost for your group. - [Airline Miles Value Calculator](https://mathva.com/travel/airline-miles-value-calculator.md): Calculate how many cents per mile you get from an award flight and whether it beats paying cash, compared with typical program values. - [Points Transfer Value Calculator](https://mathva.com/travel/points-transfer-value-calculator.md): Compare transferring credit card points to airline or hotel partners against booking through the travel portal, in cents per point. - [Group Travel Budget Splitter](https://mathva.com/travel/group-travel-budget-splitter.md): Split group trip expenses fairly — who paid what, who shares each cost — and get the fewest payments needed to settle up. - [Trip Cost per Person Calculator](https://mathva.com/travel/trip-cost-per-person-calculator.md): Estimate total trip cost and cost per person per day, splitting shared lodging and car costs across your group. - [Tipping Calculator by Country](https://mathva.com/travel/tipping-calculator-by-country.md): See how much to tip in restaurants, taxis and hotels in 40+ countries, and calculate the tip and split for your bill. - [Road Trip Fuel and Time Planner](https://mathva.com/travel/road-trip-fuel-and-time-planner.md): Plan a road trip: driving days, daily schedule, fuel stops, gas cost and hotel nights, with costs split per person. - [Driving Distance and Cost Calculator](https://mathva.com/travel/driving-distance-and-cost-calculator.md): Estimate driving distance, time and fuel cost between cities, and compare the cost of driving versus flying for your group. - [Visa-free Country Checker](https://mathva.com/travel/visa-free-country-checker.md): Check visa requirements for popular destinations with a US, UK, Canadian, Australian, EU or Indian passport — visa-free, ETA, e-visa or visa required. - [Passport 6-month Rule Checker](https://mathva.com/travel/passport-6-month-rule-checker.md): Check if your passport meets the six-month validity rule (or other validity requirements) for your destination and trip dates. - [Schengen 90/180 Day Calculator](https://mathva.com/travel/schengen-90-180-day-calculator.md): Count your days in the Schengen Area under the 90/180-day rule, check a planned trip for overstays and find your latest legal exit date. - [Packing Weight Calculator](https://mathva.com/travel/packing-weight-calculator.md): Add up your luggage weight item by item, compare it with carry-on or checked bag limits, and find the heaviest things to cut. - [Altitude Acclimatization Planner](https://mathva.com/travel/altitude-acclimatization-planner.md): Build a safe high-altitude acclimatization schedule for treks and climbs, with daily sleeping altitudes, rest days and oxygen levels. - [Sunrise and Sunset Time by Location](https://mathva.com/travel/sunrise-and-sunset-time-by-location.md): Find sunrise, sunset, solar noon, day length, twilight and golden hour times for 100+ cities or any latitude and longitude on any date. - [Best Time to Book Flight Estimator](https://mathva.com/travel/best-time-to-book-flight-estimator.md): Find the best time to book a flight for your departure date — domestic, short-haul or long-haul international, in normal, peak or holiday season. ## Dates, Time & Countdown Age, date differences, business days, time cards, time zones and timestamps. - [Exact Age Calculator](https://mathva.com/dates-time/exact-age-calculator.md): Calculate your exact age in years, months and days — plus total weeks, days, hours and your next birthday countdown. - [Date Difference Calculator](https://mathva.com/dates-time/date-difference-calculator.md): Count the days between two dates, plus weeks, months and years, weekdays, weekends and business days excluding public holidays. - [Business Days Calculator](https://mathva.com/dates-time/business-days-calculator.md): Count business days between two dates or add business days to a date, excluding weekends and US, UK, Canadian or other public holidays. - [Time Card Calculator](https://mathva.com/dates-time/time-card-calculator.md): Free time card calculator: total weekly hours from clock-in and clock-out times with breaks, overtime and gross pay — overnight shifts supported. - [Add or Subtract Days from a Date](https://mathva.com/dates-time/add-or-subtract-days-from-a-date.md): Add or subtract days, weeks, months and years from any date — or count forward in business days — to find the exact resulting date. - [Working Days with Public Holidays Calculator](https://mathva.com/dates-time/working-days-with-public-holidays-calculator.md): Count working days between two dates after removing weekends, national public holidays (US, UK, Canada, Australia, Germany, France, India) and your own days off. - [Shareable Countdown Timer Generator](https://mathva.com/dates-time/shareable-countdown-timer-generator.md): Create a live countdown timer to any date, time and time zone — share it with a link or copy an embeddable countdown widget for your site. - [Week Number Calculator](https://mathva.com/dates-time/week-number-calculator.md): Find the ISO 8601 week number for any date, plus the US week number, week start and end dates, day of year and quarter. - [Days Until Retirement Counter](https://mathva.com/dates-time/days-until-retirement-counter.md): Count down the days, workdays, weekends and paychecks until you retire, and see how much of your career is already behind you. - [Days Alive Counter](https://mathva.com/dates-time/days-alive-counter.md): See how many days, hours, minutes and seconds you’ve been alive — updating live — plus heartbeats and your next 10,000-day or billion-second milestone. - [Half Birthday Calculator](https://mathva.com/dates-time/half-birthday-calculator.md): Find your half birthday — exactly six months after your birthday — with a countdown and the alternate 182-day date. - [Leap Year Checker](https://mathva.com/dates-time/leap-year-checker.md): Check whether any year is a leap year, see why, find the previous and next leap years and list all leap years in a range. - [Time Duration Calculator](https://mathva.com/dates-time/time-duration-calculator.md): Calculate the duration between two times or dates in hours and minutes, or add and subtract hours and minutes from a time. - [Military Time Converter](https://mathva.com/dates-time/military-time-converter.md): Convert military time to standard AM/PM time and back, with the spoken form and a full 24-hour conversion chart. - [Unix Timestamp Converter](https://mathva.com/dates-time/unix-timestamp-converter.md): Convert Unix timestamps (seconds or milliseconds) to human-readable dates in any time zone, and dates back to epoch time — with code snippets. - [Epoch to Date Converter](https://mathva.com/dates-time/epoch-to-date-converter.md): Batch-convert epoch times to dates: Unix seconds, milliseconds, microseconds, Excel serial dates, Windows FILETIME/LDAP, Apple Cocoa and GPS time. - [Cron Expression Explainer](https://mathva.com/dates-time/cron-expression-explainer.md): Explain any cron expression in plain English and list the next run times in your time zone — supports ranges, steps, lists, names and @daily macros. - [Multi-timezone Meeting Planner](https://mathva.com/dates-time/multi-timezone-meeting-planner.md): Check a proposed meeting time for every participant’s time zone, flag nights and weekends, and copy local times and a calendar snippet. - [Bedtime / Wake Time Calculator](https://mathva.com/dates-time/bedtime-wake-time-calculator.md): Work out what time to go to bed for your wake-up time based on recommended sleep hours for your age, and estimate your weekly sleep debt. - [Pomodoro Session Planner](https://mathva.com/dates-time/pomodoro-session-planner.md): Plan a Pomodoro work session: turn your task list into a timed schedule of focus blocks and breaks with an exact finish time. ## Math, Science & Engineering Percentages, fractions, statistics, algebra, geometry, electronics, chemistry and physics. - [Scientific Calculator](https://mathva.com/math-science/scientific-calculator.md): Free online scientific calculator with trig (DEG/RAD), logs, powers, roots, factorials, memory keys and a printable calculation tape. - [Online Calculator with Tape](https://mathva.com/math-science/online-calculator-with-tape.md): Simple online calculator with a running tape you can print or copy, memory keys, percent and keyboard support — free and works offline. - [Unit Converter (All Units)](https://mathva.com/math-science/unit-converter.md): Universal unit converter: convert length, weight, volume, area, speed, temperature, energy, power, pressure, data, time, frequency and fuel economy in one place. - [Graphing Calculator](https://mathva.com/math-science/graphing-calculator.md): Free online graphing calculator: plot up to 5 functions, move a parameter slider, and find roots, intercepts and maximum/minimum values. - [Percentage Calculator (All Types)](https://mathva.com/math-science/percentage-calculator.md): Free percentage calculator for every type: X% of Y, what percent X is of Y, percent change, percent difference, and increasing or decreasing by a percent. - [Standard Deviation Calculator](https://mathva.com/math-science/standard-deviation-calculator.md): Calculate sample or population standard deviation, variance, mean, standard error and coefficient of variation with a step-by-step table. - [Roman Numeral Converter](https://mathva.com/math-science/roman-numeral-converter.md): Convert numbers to Roman numerals and Roman numerals back to numbers (1–3999), with a breakdown and validation of non-standard numerals. - [Percentage Increase and Decrease Calculator](https://mathva.com/math-science/percentage-increase-and-decrease-calculator.md): Calculate the percentage increase or decrease between two numbers, or find the original value before a percent change. - [Ratio Calculator and Simplifier](https://mathva.com/math-science/ratio-calculator-and-simplifier.md): Simplify ratios with two or more parts, split a total by a ratio, scale ratios up or down and list equivalent ratios. - [Proportion Solver](https://mathva.com/math-science/proportion-solver.md): Solve proportions a/b = c/d for the missing value using cross-multiplication, with the check and steps shown. - [Fraction Calculator](https://mathva.com/math-science/fraction-calculator.md): Add, subtract, multiply and divide fractions and mixed numbers with step-by-step working, simplified results and decimal answers. - [Fraction to Decimal Converter](https://mathva.com/math-science/fraction-to-decimal-converter.md): Convert fractions to decimals (showing repeating digits) and decimals — including repeating decimals — back to simplified fractions. - [Scientific Notation Converter](https://mathva.com/math-science/scientific-notation-converter.md): Convert numbers to and from scientific notation, E notation and engineering notation, keeping significant figures and SI prefixes. - [Significant Figures Calculator](https://mathva.com/math-science/significant-figures-calculator.md): Count significant figures in any number and round to a chosen number of sig figs, with the rules explained for leading and trailing zeros. - [Rounding Calculator](https://mathva.com/math-science/rounding-calculator.md): Round numbers to decimal places or to the nearest ten, hundred or thousand, comparing half-up, banker’s, ceiling, floor and truncation methods. - [Mean Median Mode Calculator](https://mathva.com/math-science/mean-median-mode-calculator.md): Find the mean, median, mode and range of a data set, plus quartiles, interquartile range, outliers and a frequency chart. - [Z-score Calculator](https://mathva.com/math-science/z-score-calculator.md): Calculate a z-score, percentile and one- or two-tailed probabilities from a value, mean and standard deviation — or find the value for a percentile. - [Confidence Interval Calculator](https://mathva.com/math-science/confidence-interval-calculator.md): Calculate confidence intervals for a mean (t or z) or a proportion (Wilson and Wald), with margin of error and critical values. - [Sample Size Calculator](https://mathva.com/math-science/sample-size-calculator.md): Calculate the sample size needed for a survey or study from confidence level, margin of error, expected proportion or standard deviation and population size. - [A/B Test Significance Calculator](https://mathva.com/math-science/ab-test-significance-calculator.md): Check if your A/B test result is statistically significant: conversion rates, lift, p-value, z-score, confidence interval and required sample size. - [Correlation Calculator](https://mathva.com/math-science/correlation-calculator.md): Calculate Pearson’s correlation coefficient r, R², Spearman’s rank correlation and the p-value for paired x, y data. - [Linear Regression Calculator](https://mathva.com/math-science/linear-regression-calculator.md): Fit a least-squares linear regression line to x, y data: slope, intercept, R², p-value, residuals, a chart and predictions with intervals. - [Probability Calculator](https://mathva.com/math-science/probability-calculator.md): Calculate probabilities for two events (and, or, not, conditional), the chance of at least one success in n tries, and binomial probabilities. - [Combination and Permutation Calculator](https://mathva.com/math-science/combination-and-permutation-calculator.md): Calculate combinations (nCr) and permutations (nPr), with or without repetition, using exact big-number arithmetic. - [Dice Probability Calculator](https://mathva.com/math-science/dice-probability-calculator.md): Calculate dice probabilities for any number of dice and sides — exact, at least or at most a target sum — with the full distribution. - [Quadratic Equation Solver](https://mathva.com/math-science/quadratic-equation-solver.md): Solve quadratic equations ax² + bx + c = 0 with the quadratic formula: real or complex roots, discriminant, vertex, factored form, steps and a graph. - [System of Equations Solver](https://mathva.com/math-science/system-of-equations-solver.md): Solve systems of linear equations with 2 to 8 variables using Gaussian elimination — unique, no or infinitely many solutions, with the reduced matrix. - [Matrix Calculator](https://mathva.com/math-science/matrix-calculator.md): Matrix calculator: add, subtract and multiply matrices, and find the determinant, inverse, transpose, rank and reduced row echelon form. - [Derivative Calculator](https://mathva.com/math-science/derivative-calculator.md): Derivative calculator: differentiate f(x) symbolically, evaluate the slope at a point, get the second derivative and tangent line, with a graph. - [Integral Calculator](https://mathva.com/math-science/integral-calculator.md): Integral calculator: definite integrals with high-precision numeric integration, plus the antiderivative for polynomials, trig, exponential and log functions. - [Limit Calculator](https://mathva.com/math-science/limit-calculator.md): Limit calculator: estimate one- and two-sided limits of f(x) as x approaches a number or infinity, with a table of approaching values. - [Slope and Midpoint Calculator](https://mathva.com/math-science/slope-and-midpoint-calculator.md): Find the slope, midpoint, distance and line equation (slope-intercept, point-slope and standard form) between two points. - [Distance between Two Points Calculator](https://mathva.com/math-science/distance-between-two-points-calculator.md): Calculate the distance between two points in 2D or 3D with the distance formula, including the exact radical form, midpoint and Manhattan distance. - [Triangle Solver](https://mathva.com/math-science/triangle-solver.md): Solve any triangle from SSS, SAS, ASA, AAS or SSA: all sides, angles, area, perimeter, type and the ambiguous SSA case. - [Circle Area and Circumference Calculator](https://mathva.com/math-science/circle-area-and-circumference-calculator.md): Calculate a circle’s area, circumference, diameter and radius from any one of them, plus arc length and sector area. - [Volume of Shapes Calculator](https://mathva.com/math-science/volume-of-shapes-calculator.md): Calculate the volume of a cube, box, cylinder, cone, sphere, hemisphere, pyramid, prism, frustum, capsule, ellipsoid or torus, with liters and gallons. - [Surface Area Calculator](https://mathva.com/math-science/surface-area-calculator.md): Calculate total and lateral surface area of cubes, boxes, cylinders, cones, spheres, hemispheres, pyramids, frustums, capsules and tori. - [Pythagorean Theorem Calculator](https://mathva.com/math-science/pythagorean-theorem-calculator.md): Pythagorean theorem calculator: find the hypotenuse or a missing leg of a right triangle, check if three sides form a right triangle, with angles and area. - [Trigonometry Calculator](https://mathva.com/math-science/trigonometry-calculator.md): Calculate sin, cos, tan, csc, sec and cot for any angle in degrees or radians, with exact values for special angles, plus inverse trig functions. - [Logarithm Calculator](https://mathva.com/math-science/logarithm-calculator.md): Calculate logarithms in any base — natural log (ln), log base 10 and log base 2 — with the change-of-base formula and a check. - [GCD and LCM Calculator](https://mathva.com/math-science/gcd-and-lcm-calculator.md): Find the greatest common divisor (GCD/GCF/HCF) and least common multiple (LCM) of two or more numbers, with prime factorizations and Euclid’s steps. - [Prime Number Checker](https://mathva.com/math-science/prime-number-checker.md): Check whether a number is prime (up to 24 digits), get its prime factorization, the previous and next primes, and list primes in a range. - [Number Base Converter](https://mathva.com/math-science/number-base-converter.md): Convert numbers between binary, octal, decimal, hexadecimal and any base from 2 to 36 — including huge numbers and two’s complement for negatives. - [Ohm's Law Calculator](https://mathva.com/math-science/ohms-law-calculator.md): Ohm’s law calculator: enter any two of voltage, current, resistance and power to find the other two, with a resistor power rating suggestion. - [Resistor Color Code Calculator](https://mathva.com/math-science/resistor-color-code-calculator.md): Decode 4, 5 and 6-band resistor color codes into resistance, tolerance and temperature coefficient, with a color swatch and reference chart. - [Capacitor Code Calculator](https://mathva.com/math-science/capacitor-code-calculator.md): Decode ceramic and film capacitor codes like 104, 473J or 4R7 into pF, nF and µF with tolerance — or find the code for a value. - [LED Resistor Calculator](https://mathva.com/math-science/led-resistor-calculator.md): Calculate the current-limiting resistor for one or more LEDs from supply voltage, LED forward voltage and current, with the nearest standard value and wattage. - [Series and Parallel Resistance Calculator](https://mathva.com/math-science/series-and-parallel-resistance-calculator.md): Calculate total resistance, capacitance or inductance for components in series and in parallel. - [Power Factor Calculator](https://mathva.com/math-science/power-factor-calculator.md): Calculate power factor, apparent and reactive power, phase angle and the capacitor kVAR needed to correct power factor for single- or three-phase loads. - [Torque Unit Converter](https://mathva.com/math-science/torque-unit-converter.md): Convert torque between newton-meters, pound-feet, pound-inches, ounce-inches, kilogram-force meters and more. - [Pressure Unit Converter](https://mathva.com/math-science/pressure-unit-converter.md): Convert pressure between psi, bar, kPa, MPa, atm, mmHg (torr), inHg, inches of water and more. - [Flow Rate Calculator](https://mathva.com/math-science/flow-rate-calculator.md): Calculate flow rate from pipe diameter and velocity, velocity from flow rate, or convert between GPM, L/min, m³/h, CFS and CFM. - [Pipe Volume Calculator](https://mathva.com/math-science/pipe-volume-calculator.md): Calculate the volume of liquid a pipe holds in gallons, liters and cubic feet from its inner diameter and length, plus the weight when full. - [Pump Head Calculator](https://mathva.com/math-science/pump-head-calculator.md): Calculate pump total dynamic head (TDH) and horsepower from flow, lift, pipe length, diameter, material, fittings and discharge pressure. - [Molar Mass Calculator](https://mathva.com/math-science/molar-mass-calculator.md): Calculate the molar mass (molecular weight) of any chemical formula with element-by-element breakdown, mass percent composition and grams-to-moles conversion. - [Molarity and Dilution Calculator](https://mathva.com/math-science/molarity-and-dilution-calculator.md): Molarity calculator: find grams of solute for a solution, molarity from mass and volume, or dilution volumes with C₁V₁ = C₂V₂. - [pH Calculator](https://mathva.com/math-science/ph-calculator.md): Calculate pH, pOH, [H⁺] and [OH⁻] from any one of them, or the pH of a weak acid from its concentration and Ka. - [Ideal Gas Law Calculator](https://mathva.com/math-science/ideal-gas-law-calculator.md): Solve the ideal gas law PV = nRT for pressure, volume, moles or temperature with automatic unit conversions. - [Half-life Calculator](https://mathva.com/math-science/half-life-calculator.md): Half-life calculator: find the amount remaining, time elapsed or half-life for radioactive decay, drugs or any exponential decay, with the decay constant. - [Projectile Motion Calculator](https://mathva.com/math-science/projectile-motion-calculator.md): Projectile motion calculator: range, flight time, maximum height and impact speed from launch speed, angle and height, with a trajectory chart. - [Free Fall Calculator](https://mathva.com/math-science/free-fall-calculator.md): Free fall calculator: time to fall, impact velocity and distance for a dropped object on Earth, the Moon or Mars, without air resistance. - [Force and Acceleration Calculator](https://mathva.com/math-science/force-and-acceleration-calculator.md): Newton’s second law calculator: solve F = ma for force, mass or acceleration, with conversions to pound-force, kilogram-force and g. - [Density Calculator](https://mathva.com/math-science/density-calculator.md): Density calculator: solve ρ = m/V for density, mass or volume, with kg/m³ and lb/ft³ conversions, float-or-sink and common material comparison. - [Speed Distance Time Calculator](https://mathva.com/math-science/speed-distance-time-calculator.md): Speed, distance and time calculator: solve for any one from the other two with miles, kilometers, mph, km/h, m/s and knots. ## Education & Students GPA, final grades, college costs, study plans, citations and attendance. - [GPA Calculator (Weighted and Unweighted)](https://mathva.com/education/gpa-calculator.md): Calculate weighted and unweighted high school or college GPA from letter or percentage grades, credits and honors or AP course levels. - [Final Exam Grade Needed Calculator](https://mathva.com/education/final-exam-grade-needed-calculator.md): Find out what score you need on your final exam to get the class grade you want, based on your current grade and the exam’s weight. - [Semester to Cumulative GPA Calculator](https://mathva.com/education/semester-to-cumulative-gpa-calculator.md): Calculate your new cumulative GPA after a semester, and the GPA you need in future credits to reach a target GPA. - [Grade Percentage Calculator](https://mathva.com/education/grade-percentage-calculator.md): Calculate your class grade percentage and letter grade from weighted categories or total points earned, with each category’s contribution. - [Test Score Curve Calculator](https://mathva.com/education/test-score-curve-calculator.md): Curve test scores with a flat bonus, top-score scaling, square-root curve or bell curve, and compare raw and curved grades. - [Class Rank Percentile Calculator](https://mathva.com/education/class-rank-percentile-calculator.md): Convert your class rank into a percentile and top-percent figure, with decile, quartile and how many students rank below you. - [College Total Cost Calculator](https://mathva.com/education/college-total-cost-calculator.md): Estimate the total cost of college over 4 years — tuition, housing, food, books and personal costs — with yearly increases and net cost after aid. - [Student Budget Planner](https://mathva.com/education/student-budget-planner.md): Plan a monthly college student budget — income from jobs, family and aid versus rent, food, books and fun — with term totals and the 50/30/20 check. - [Scholarship Gap Calculator](https://mathva.com/education/scholarship-gap-calculator.md): Find your college funding gap after grants, scholarships, savings and federal student loan limits, with your financial need and aid breakdown. - [Study Hours Planner](https://mathva.com/education/study-hours-planner.md): Plan weekly study hours for each course from credit hours and difficulty, with a daily study schedule and total academic workload. - [Reading Time Estimator](https://mathva.com/education/reading-time-estimator.md): Estimate how long it takes to read any text, word count or number of pages at your reading speed — for essays, books, articles and textbooks. - [Word Count to Speech Time Converter](https://mathva.com/education/word-count-to-speech-time-converter.md): Convert word count to speaking time for speeches and presentations, or find how many words to write for a time limit. - [Citation Generator (APA/MLA/Chicago)](https://mathva.com/education/citation-generator.md): Free citation generator for APA 7, MLA 9 and Chicago style — cite websites, books and journal articles with in-text citations and hanging indents. - [Spaced Repetition Scheduler](https://mathva.com/education/spaced-repetition-scheduler.md): Create a spaced repetition review schedule with expanding intervals or the SM-2 algorithm, so you review material just before you forget it. - [Assignment Deadline Planner](https://mathva.com/education/assignment-deadline-planner.md): Break an assignment or project into milestones with start and finish dates, hours per day and a safety buffer before the deadline. - [Exam Countdown Planner](https://mathva.com/education/exam-countdown-planner.md): Count down to your exams and plan study time: days left, study hours needed per day for each exam and whether your schedule is realistic. - [Attendance Percentage Calculator](https://mathva.com/education/attendance-percentage-calculator.md): Calculate your attendance percentage, how many classes you can skip, or how many you must attend in a row to reach 75% (or any requirement). - [CGPA to Percentage Converter](https://mathva.com/education/cgpa-to-percentage-converter.md): Convert CGPA to percentage using CBSE, AICTE, VTU, Mumbai University, Anna University and other formulas, with division/class. - [Class Schedule Conflict Checker](https://mathva.com/education/class-schedule-conflict-checker.md): Check a class schedule for time conflicts and tight transitions, see a weekly day-by-day view and total hours in class. - [Syllabus Workload Estimator](https://mathva.com/education/syllabus-workload-estimator.md): Estimate a course’s real weekly workload from its syllabus — readings, writing, problem sets, exams, videos and projects — in hours per week. ## SEO, Marketing & Content SEO previews, schema, UTM links, readability and ad-budget math. - [Keyword Density Checker](https://mathva.com/marketing-seo/keyword-density-checker.md): Check keyword density and the most-used words and phrases in your content to avoid under- or over-optimization. - [Meta Title and Description Length Preview](https://mathva.com/marketing-seo/meta-title-and-description-length-preview.md): Check your meta title and description length in characters and estimated pixels, with a live Google preview. - [SERP Snippet Preview Tool](https://mathva.com/marketing-seo/serp-snippet-preview-tool.md): Preview how your page title, URL and meta description appear in Google search results before you publish. - [Robots.txt Generator](https://mathva.com/marketing-seo/robots-txt-generator.md): Generate a valid robots.txt file with disallowed paths, sitemap location and optional AI crawler rules. - [XML Sitemap Generator](https://mathva.com/marketing-seo/xml-sitemap-generator.md): Generate an XML sitemap from a list of URLs with lastmod, changefreq and priority, ready to upload. - [Schema Markup Generator](https://mathva.com/marketing-seo/schema-markup-generator.md): Generate JSON-LD schema markup for Organization, LocalBusiness, Article, Product and FAQPage — copy and paste into your site. - [Open Graph Tag Generator](https://mathva.com/marketing-seo/open-graph-tag-generator.md): Generate Open Graph and Twitter Card meta tags so your pages look great when shared on social media. - [UTM Link Builder](https://mathva.com/marketing-seo/utm-link-builder.md): Build UTM-tagged campaign URLs for Google Analytics with source, medium, campaign, term and content. - [Redirect Chain Checker](https://mathva.com/marketing-seo/redirect-chain-checker.md): Redirect chain checker: paste curl or DevTools headers to map every redirect hop, status code and final URL, and spot loops, 302s, long chains and HTTPS downgrades. - [Domain Age Checker](https://mathva.com/marketing-seo/domain-age-checker.md): Domain age checker: look up when any domain was first registered, its expiry date, registrar, status and name servers using live RDAP registry data. - [Website Speed Score Checker](https://mathva.com/marketing-seo/website-speed-score-checker.md): Website speed test: get a live Google PageSpeed Insights performance score with Core Web Vitals (LCP, INP, CLS), lab metrics and top fixes for mobile or desktop. - [Readability Score Checker](https://mathva.com/marketing-seo/readability-score-checker.md): Score readability with Flesch Reading Ease, Flesch-Kincaid grade level and Gunning Fog, plus reading time. - [Headline Analyzer](https://mathva.com/marketing-seo/headline-analyzer.md): Analyze a headline’s length, power words, numbers and structure, and get a score with suggestions to improve click-through. - [CTR by SERP Position Estimator](https://mathva.com/marketing-seo/ctr-by-serp-position-estimator.md): Estimate organic clicks and traffic value by Google ranking position using average click-through rates. - [Ad Budget Planner](https://mathva.com/marketing-seo/ad-budget-planner.md): Plan a monthly and daily ad budget from your conversion goal, conversion rate and cost per click. - [CPM / CPC / CPA Converter](https://mathva.com/marketing-seo/cpm-cpc-cpa-converter.md): Convert between CPM, CPC and CPA and calculate CTR and conversion rate from spend, impressions, clicks and conversions. - [Email Subject Line Tester](https://mathva.com/marketing-seo/email-subject-line-tester.md): Test an email subject line for length, spam-trigger words, personalization, emoji and mobile truncation. - [Email List ROI Calculator](https://mathva.com/marketing-seo/email-list-roi-calculator.md): Estimate email marketing revenue and ROI from list size, send frequency, click rate, conversion rate and order value. - [Content Calendar Generator](https://mathva.com/marketing-seo/content-calendar-generator.md): Generate a content calendar that rotates your content pillars across publishing days — export as CSV. - [Blog Post Outline Generator](https://mathva.com/marketing-seo/blog-post-outline-generator.md): Generate an SEO-friendly blog post outline with title, headings, FAQs and an on-page checklist for any topic. ## Social Media & Creator Engagement rates, creator earnings, sponsorship pricing and growth projections. - [Fancy Text Generator (Fonts and Symbols)](https://mathva.com/social-media/fancy-text-generator.md): Fancy text generator: turn text into bold, italic, script, gothic, bubble, monospace and upside-down Unicode fonts plus symbols to copy and paste into bios. - [Engagement Rate Calculator](https://mathva.com/social-media/engagement-rate-calculator.md): Calculate social media engagement rate by followers and by reach for Instagram, TikTok, YouTube, Facebook, X and LinkedIn, with platform benchmarks. - [Influencer Rate Card Calculator](https://mathva.com/social-media/influencer-rate-card-calculator.md): Build an influencer rate card: suggested prices for posts, reels, stories, TikToks and YouTube integrations from followers, engagement, views and niche. - [YouTube Earnings Estimator](https://mathva.com/social-media/youtube-earnings-estimator.md): Estimate YouTube earnings from monthly views, channel niche, audience geography and Shorts views using realistic RPM ranges. - [TikTok Earnings Estimator](https://mathva.com/social-media/tiktok-earnings-estimator.md): Estimate TikTok earnings from the Creator Rewards Program, brand deals, TikTok Shop affiliate commissions and LIVE gifts. - [Instagram Earnings Estimator](https://mathva.com/social-media/instagram-earnings-estimator.md): Estimate Instagram income from sponsored posts and reels, subscriptions and affiliate commissions based on followers, engagement and niche. - [Twitch Revenue Calculator](https://mathva.com/social-media/twitch-revenue-calculator.md): Calculate Twitch streamer revenue from Tier 1–3 and Prime subscriptions, bits, and ads based on viewers, hours streamed and revenue split. - [Patreon Earnings Calculator](https://mathva.com/social-media/patreon-earnings-calculator.md): Calculate Patreon earnings after platform and payment processing fees from your membership tiers, with a 12-month projection including churn. - [Ad Revenue Share Calculator](https://mathva.com/social-media/ad-revenue-share-calculator.md): Calculate ad revenue for websites and videos from views, ads per page, fill rate, CPM and the revenue share of AdSense, Mediavine, YouTube and others. - [Follower Growth Projection Tool](https://mathva.com/social-media/follower-growth-projection-tool.md): Project follower growth over time with percentage or fixed monthly growth and unfollows, and see when you’ll reach your follower goal. - [Best Posting Time Calculator](https://mathva.com/social-media/best-posting-time-calculator.md): Find the best times to post on Instagram, TikTok, YouTube, Facebook, X, LinkedIn and Pinterest, converted from your audience’s time zone to yours. - [Hashtag Limit Checker](https://mathva.com/social-media/hashtag-limit-checker.md): Check your caption’s hashtag count and character length against Instagram, TikTok, X, LinkedIn, YouTube, Facebook and Threads limits, and find duplicates. - [Video Length to File Size Estimator](https://mathva.com/social-media/video-length-to-file-size-estimator.md): Estimate video file size from length, resolution or bitrate and audio quality — plus upload time and how many videos fit on a memory card. - [Aspect Ratio Calculator](https://mathva.com/social-media/aspect-ratio-calculator.md): Calculate and simplify aspect ratios from width and height, resize while keeping proportions and find the right size for YouTube, Reels and posts. - [Frame Rate and Duration Calculator](https://mathva.com/social-media/frame-rate-and-duration-calculator.md): Convert between video duration and frame count at any frame rate, show SMPTE timecode, and calculate speed changes when conforming frame rates. - [Subscriber Milestone Predictor](https://mathva.com/social-media/subscriber-milestone-predictor.md): Predict when you’ll reach 1K, 10K, 100K and 1M subscribers or followers based on your recent monthly growth and acceleration. - [Sponsorship Deal Value Calculator](https://mathva.com/social-media/sponsorship-deal-value-calculator.md): Price a brand sponsorship deal from expected views, niche CPM, integration type, usage rights, exclusivity, extra deliverables and production costs. - [Merch Profit Calculator](https://mathva.com/social-media/merch-profit-calculator.md): Calculate creator merch profit per item and per month after product cost, shipping, platform fees and fixed costs, with break-even units. - [Podcast Downloads to CPM Revenue Calculator](https://mathva.com/social-media/podcast-downloads-to-cpm-revenue-calculator.md): Estimate podcast advertising income from downloads per episode, ad slots, pre/mid/post-roll CPMs, sell-through rate and network commission. - [Newsletter Sponsorship Pricing Calculator](https://mathva.com/social-media/newsletter-sponsorship-pricing-calculator.md): Price newsletter sponsorships — primary, secondary and classified slots — from subscribers, open rate, click rate and audience niche. - [Creator Tax Set-aside Calculator](https://mathva.com/social-media/creator-tax-set-aside-calculator.md): Calculate how much creators and influencers should set aside for taxes — self-employment, federal and state — with quarterly estimated payments. ## Developer Tools JSON, regex, Base64, hashes, JWTs, colors, CSS generators, subnets and DNS. - [JSON Formatter and Validator](https://mathva.com/developer/json-formatter-and-validator.md): Format, beautify, minify and validate JSON online with exact error line and column, key sorting and auto-fix for common mistakes. - [Regex Tester and Explainer](https://mathva.com/developer/regex-tester-and-explainer.md): Test regular expressions online with live match highlighting, capture groups, replace preview and a plain-English token-by-token explanation. - [Base64 Encoder and Decoder](https://mathva.com/developer/base64-encoder-and-decoder.md): Encode text to Base64 and decode Base64 to text online with full UTF-8 and emoji support, URL-safe Base64 and MIME line wrapping. - [Color Picker and HEX/RGB/HSL Converter](https://mathva.com/developer/color-picker-and-hex-rgb-hsl-converter.md): Color picker and converter: HEX, RGB, HSL, HSV and CMYK values, WCAG contrast checker, complementary and triadic palettes and a tint/shade scale with CSS variables. - [Password Generator](https://mathva.com/developer/password-generator.md): Generate strong random passwords, memorable passphrases or PINs with custom length and character sets, showing entropy and crack time — created securely in your browser. - [Word Counter and Text Tools](https://mathva.com/developer/text-tools-word-counter.md): Free online text tools: word and character counter, remove duplicate lines, sort, reverse, trim, find and replace, add line numbers and change case. - [JSON to CSV Converter](https://mathva.com/developer/json-to-csv-converter.md): Convert JSON arrays to CSV online — flattens nested objects into dot-notation columns, handles quoting and supports comma, semicolon, tab or pipe delimiters. - [YAML to JSON Converter](https://mathva.com/developer/yaml-to-json-converter.md): Convert YAML to JSON and JSON to YAML online, with validation and clear line-numbered errors for Kubernetes, Docker Compose and CI configs. - [XML Formatter](https://mathva.com/developer/xml-formatter.md): Format, pretty-print, minify and check XML online — indentation, well-formedness errors, element and attribute counts. - [SQL Formatter](https://mathva.com/developer/sql-formatter.md): Format and beautify SQL queries online — keyword casing, clause line breaks and indentation for SELECT, JOIN, WHERE, GROUP BY and more. - [Cron Expression Builder](https://mathva.com/developer/cron-expression-builder.md): Build cron expressions visually — pick minutes, hours, days, months and weekdays — then copy for crontab, GitHub Actions or Kubernetes with next run times. - [UUID Generator](https://mathva.com/developer/uuid-generator.md): Generate random UUID v4 or time-ordered UUID v7 identifiers in bulk, with uppercase, hyphen and brace options — created securely in your browser. - [Hash Generator (MD5/SHA)](https://mathva.com/developer/hash-generator.md): Generate MD5, SHA-1, SHA-256, SHA-384, SHA-512 and CRC-32 hashes — plus HMAC with a secret key — in hex and Base64, entirely in your browser. - [URL Encoder and Decoder](https://mathva.com/developer/url-encoder-and-decoder.md): URL encode and decode text online (percent-encoding), choose component or full-URL encoding, and parse URLs into host, path and query parameters. - [JWT Decoder](https://mathva.com/developer/jwt-decoder.md): Decode JWT tokens online: view the header and payload, check exp/iat/nbf dates and expiry, and verify HS256/HS384/HS512 signatures locally. - [Text Diff Checker](https://mathva.com/developer/text-diff-checker.md): Compare two texts and highlight differences line by line — added, removed and unchanged lines, similarity score and unified diff output. - [Markdown Previewer](https://mathva.com/developer/markdown-previewer.md): Live Markdown previewer and converter: write GitHub-flavored Markdown and see the rendered result plus clean HTML output instantly. - [HTML Entity Encoder](https://mathva.com/developer/html-entity-encoder.md): Encode and decode HTML entities online — escape <, >, & and quotes to prevent XSS, or convert named and numeric entities back to text. - [CSS Gradient Generator](https://mathva.com/developer/css-gradient-generator.md): CSS gradient generator: design linear, radial and conic gradients with up to three color stops, preview live and copy the CSS. - [Box Shadow Generator](https://mathva.com/developer/box-shadow-generator.md): CSS box-shadow generator with live preview: set offsets, blur, spread, color, opacity, inset and a layered soft shadow, then copy the CSS. - [Flexbox and Grid Playground](https://mathva.com/developer/flexbox-and-grid-playground.md): Interactive Flexbox and CSS Grid playground: change direction, wrap, justify, align, gap and grid templates and see the layout update with copyable CSS. - [Border Radius Generator](https://mathva.com/developer/border-radius-generator.md): CSS border-radius generator: round each corner individually in px, % or rem with a live shape preview and optimized shorthand CSS. - [Favicon Size Checker](https://mathva.com/developer/favicon-size-checker.md): Check which favicon sizes your site needs — ICO, SVG, Apple touch icon, Android and PWA icons — and get the exact HTML head tags and web manifest. - [Lorem Ipsum Generator](https://mathva.com/developer/lorem-ipsum-generator.md): Generate lorem ipsum placeholder text by paragraphs, sentences, words or list items, with optional HTML tags — copy it with one click. - [Password Strength Checker](https://mathva.com/developer/password-strength-checker.md): Check password strength privately in your browser: entropy, crack-time estimates for online and offline attacks, and warnings about common patterns. - [.htaccess Generator](https://mathva.com/developer/htaccess-generator.md): Generate an Apache .htaccess file: force HTTPS, www redirects, 301 redirects, compression, browser caching, security headers, hotlink protection and IP blocking. - [Nginx Config Generator](https://mathva.com/developer/nginx-config-generator.md): Generate an Nginx server block for static sites, SPAs, PHP or reverse-proxied apps with HTTPS, www redirects, gzip, caching and security headers. - [Docker Compose Generator](https://mathva.com/developer/docker-compose-generator.md): Generate a docker-compose.yml for your stack — Node, Python or PHP app with PostgreSQL, MySQL, Redis, MongoDB, Nginx and Adminer, volumes and health checks. - [Git Command Finder](https://mathva.com/developer/git-command-finder.md): Find the right Git command in plain English — undo commits, rename branches, stash changes, rebase, tag and more — with explanations and safe alternatives. - [HTTP Status Code Reference](https://mathva.com/developer/http-status-code-reference.md): HTTP status code reference: look up any code from 100 to 524 by number or keyword, with plain-English meanings and SEO impact for redirects and errors. - [Subnet / CIDR Calculator](https://mathva.com/developer/subnet-cidr-calculator.md): Subnet and CIDR calculator: network address, broadcast, usable host range, subnet and wildcard masks, binary view and subnet splitting for IPv4. - [IP Address Lookup](https://mathva.com/developer/ip-address-lookup.md): Look up any IP address or find your own public IP: approximate location, ISP, ASN, time zone and whether it’s public, private or reserved. - [DNS Record Checker](https://mathva.com/developer/dns-record-checker.md): Check DNS records for any domain — A, AAAA, CNAME, MX, TXT (SPF), NS, SOA and CAA — using a public DNS-over-HTTPS resolver. - [SSL Certificate Expiry Checker](https://mathva.com/developer/ssl-certificate-expiry-checker.md): Check when a website’s SSL/TLS certificate expires — days remaining, issuer and covered hostnames — from public Certificate Transparency logs. - [Port Number Lookup](https://mathva.com/developer/port-number-lookup.md): Look up TCP and UDP port numbers and services — SSH 22, HTTPS 443, PostgreSQL 5432, Redis 6379 and 90+ common ports — with security notes. - [User Agent Parser](https://mathva.com/developer/user-agent-parser.md): Parse any user agent string — or your own — into browser, version, operating system, device type, rendering engine and bot detection. - [Screen Resolution Tester](https://mathva.com/developer/screen-resolution-tester.md): What is my screen resolution? See your screen size in CSS and physical pixels, device pixel ratio, aspect ratio, color depth and orientation. - [Viewport Size Checker](https://mathva.com/developer/viewport-size-checker.md): Check your browser viewport size live, the active Tailwind, Bootstrap or Material breakpoint, device pixel ratio and media query preferences. - [Character and Byte Counter](https://mathva.com/developer/character-and-byte-counter.md): Count characters, bytes (UTF-8/UTF-16), code points, words and lines, with emoji-aware counts and checks against SMS, X, meta tag and database limits. - [URL Slug Generator](https://mathva.com/developer/url-slug-generator.md): Generate clean, SEO-friendly URL slugs from any title — lowercase, hyphens, accents removed, stop words and years optional, with a length limit. - [Case Converter (Camel/snake/kebab)](https://mathva.com/developer/case-converter.md): Convert text between camelCase, PascalCase, snake_case, kebab-case, SCREAMING_SNAKE, Title Case, Sentence case, UPPER, lower and more at once. ## Legal & Government Settlements, divorce, probate, copyright, patents and residency math. - [Statute of Limitations Lookup by State](https://mathva.com/legal/statute-of-limitations-lookup-by-state.md): Statute of limitations lookup by state: find the deadline to sue for personal injury, property damage, written or oral contracts, with days remaining from your date. - [Small Claims Court Limit Lookup](https://mathva.com/legal/small-claims-court-limit-lookup.md): Small claims court limit lookup by state: check the maximum amount you can sue for, typical filing fees and whether your claim fits. - [Child Support Estimator by State](https://mathva.com/legal/child-support-estimator-by-state.md): Child support estimator by state: estimate monthly child support from both parents’ incomes, number of children, parenting time, childcare and health insurance. - [Alimony Estimator](https://mathva.com/legal/alimony-estimator.md): Estimate spousal support (alimony) amount and duration using the widely cited AAML guideline formula. - [Divorce Asset Split Calculator](https://mathva.com/legal/divorce-asset-split-calculator.md): Divide marital assets and debts between spouses and calculate the equalizing payment for a 50/50 or custom split. - [Will Requirements Checker by State](https://mathva.com/legal/will-requirements-checker-by-state.md): Will requirements checker by state: see witness rules, whether handwritten (holographic) and electronic wills are valid, and self-proving affidavit options. - [Probate Cost Estimator](https://mathva.com/legal/probate-cost-estimator.md): Estimate probate costs — attorney, executor and court fees — including California’s statutory fee schedule. - [Notary Fee Lookup by State](https://mathva.com/legal/notary-fee-lookup-by-state.md): Notary fee lookup by state: find the maximum a notary can charge per signature for in-person and remote online notarization, plus travel fees. - [LLC Formation Cost by State](https://mathva.com/legal/llc-formation-cost-by-state.md): LLC formation cost by state: compare filing fees, annual report and franchise tax costs, registered agent fees and total cost over several years. - [Business Name Availability Checker](https://mathva.com/legal/business-name-availability-checker.md): Business name availability checker: test an LLC or corporation name for required designators, restricted words and distinguishability, and check .com domain availability. - [Trademark Class Finder](https://mathva.com/legal/trademark-class-finder.md): Find which of the 45 Nice trademark classes fits your product or service, and estimate USPTO filing fees per class. - [Copyright Duration Calculator](https://mathva.com/legal/copyright-duration-calculator.md): Calculate when a US copyright expires and a work enters the public domain, for individual, work-for-hire and pre-1978 works. - [Patent Fee Calculator](https://mathva.com/legal/patent-fee-calculator.md): Estimate USPTO utility patent fees — filing, search, examination, excess claims, issue and maintenance — by entity size. - [Immigration Priority Date Tracker](https://mathva.com/legal/immigration-priority-date-tracker.md): Immigration priority date tracker: compare your priority date with the Visa Bulletin cutoff for your category and country, and estimate when it becomes current. - [Green Card Timeline Estimator](https://mathva.com/legal/green-card-timeline-estimator.md): Green card timeline estimator: map each step and total wait for marriage, employment (PERM, NIW, EB-1), family and diversity visa green cards by country. - [Citizenship Physical Presence Calculator](https://mathva.com/legal/citizenship-physical-presence-calculator.md): Check the naturalization physical presence and continuous residence requirements from your green card date and trips abroad. - [Jury Duty Pay by State](https://mathva.com/legal/jury-duty-pay-by-state.md): Jury duty pay by state: see how much state courts pay jurors per day, estimate your total pay and mileage, and compare it with lost wages. - [Minimum Wage by State and City](https://mathva.com/legal/minimum-wage-by-state-and-city.md): Minimum wage by state and city for 2026: look up hourly minimum wages, overtime rates, and weekly, monthly and annual full-time pay. - [Overtime Eligibility Checker](https://mathva.com/legal/overtime-eligibility-checker.md): Check whether you are exempt or non-exempt from overtime under the federal FLSA salary and duties tests. - [Lease Break Penalty Calculator](https://mathva.com/legal/lease-break-penalty-calculator.md): Estimate the cost of breaking a lease early: remaining rent, termination fee, or re-letting costs under the landlord’s duty to mitigate. - [Eviction Notice Period Lookup](https://mathva.com/legal/eviction-notice-period-lookup.md): Eviction notice period lookup by state: find required notice days for unpaid rent and ending a month-to-month tenancy, and calculate the earliest filing date. - [Security Deposit Return Deadline Checker](https://mathva.com/legal/security-deposit-return-deadline-checker.md): Security deposit return deadline checker by state: find how many days a landlord has to return your deposit, the legal maximum and penalties for withholding. - [Traffic Ticket Points Calculator](https://mathva.com/legal/traffic-ticket-points-calculator.md): Traffic ticket points calculator: see how many license points a speeding, red light, phone, reckless or DUI ticket adds in your state and the insurance cost. - [DUI Total Cost Calculator](https://mathva.com/legal/dui-total-cost-calculator.md): Estimate the full cost of a DUI: fines, legal fees, towing, classes, ignition interlock and years of higher insurance. - [Personal Injury Settlement Estimator](https://mathva.com/legal/personal-injury-settlement-estimator.md): Estimate a personal injury settlement using the multiplier method, adjusted for fault, attorney fees and policy limits. ## Weddings, Events & Life Wedding budgets, guest lists, catering, drinks and event planning. - [Wedding Budget Calculator](https://mathva.com/weddings-events/wedding-budget-calculator.md): Split your wedding budget into categories — venue, catering, photography, attire, flowers and more — and see cost per guest. - [Wedding Guest List Manager](https://mathva.com/weddings-events/wedding-guest-list-manager.md): Manage your wedding guest list: track RSVPs, plus-ones, meal choices and headcount by side — no sign-up needed. - [Seating Chart Planner](https://mathva.com/weddings-events/seating-chart-planner.md): Create a wedding or event seating chart automatically, keeping families and friend groups together at each table. - [Catering Quantity Calculator](https://mathva.com/weddings-events/catering-quantity-calculator.md): Calculate how much food to order for a wedding or party: protein, sides, salad, rolls, appetizers and dessert. - [Bar and Drinks Quantity Calculator](https://mathva.com/weddings-events/bar-and-drinks-quantity-calculator.md): Calculate how much beer, wine, liquor, champagne and ice to buy for a wedding or party bar. - [Wedding Cake Serving Calculator](https://mathva.com/weddings-events/wedding-cake-serving-calculator.md): Calculate wedding cake servings and the best combination of tier sizes for your guest count. - [Photographer Coverage Hours Planner](https://mathva.com/weddings-events/photographer-coverage-hours-planner.md): Plan how many hours of wedding photography coverage you need and build a photo timeline for the day. - [Wedding Countdown and Timeline Builder](https://mathva.com/weddings-events/wedding-countdown-and-timeline-builder.md): Count down to your wedding day and get a planning timeline with due dates for every major task. - [Honeymoon Budget Planner](https://mathva.com/weddings-events/honeymoon-budget-planner.md): Plan your honeymoon budget — flights, lodging, food, activities and insurance — and how much to save each month. - [Wedding Gift Amount Etiquette Calculator](https://mathva.com/weddings-events/wedding-gift-amount-etiquette-calculator.md): Find out how much to spend on a wedding gift based on your relationship, attendance, plus-one and budget. - [Party Favor Budget Calculator](https://mathva.com/weddings-events/party-favor-budget-calculator.md): Calculate how many party or wedding favors to make and the total cost including packaging and spares. - [Event Ticket Pricing Calculator](https://mathva.com/weddings-events/event-ticket-pricing-calculator.md): Price event tickets to break even or hit a profit target, with fixed costs, per-attendee costs and ticketing fees. - [Venue Capacity Calculator](https://mathva.com/weddings-events/venue-capacity-calculator.md): Estimate how many guests a venue can hold for banquet, cocktail, theater or classroom setups, with a dance floor. - [Table and Chair Rental Calculator](https://mathva.com/weddings-events/table-and-chair-rental-calculator.md): Calculate how many tables, chairs and linens to rent for an event, and the total rental cost. - [Wedding Hashtag Generator](https://mathva.com/weddings-events/wedding-hashtag-generator.md): Generate personalized wedding hashtag ideas from your names, last name, year and location. ## Gaming PSU wattage, bottlenecks, FPS, sensitivity, drop rates, gacha odds and DPS. - [PSU Wattage Calculator](https://mathva.com/gaming/psu-wattage-calculator.md): Calculate the power supply (PSU) wattage your gaming PC needs from its CPU, GPU, drives, fans, cooler and overclocking, with headroom for power spikes. - [PC Bottleneck Calculator](https://mathva.com/gaming/pc-bottleneck-calculator.md): Check your PC for CPU or GPU bottlenecks: see which component limits frame rate at 1080p, 1440p or 4K for AAA, esports and simulation games. - [FPS Estimator by GPU and CPU](https://mathva.com/gaming/fps-estimator-by-gpu-and-cpu.md): Estimate FPS for your graphics card and processor by game type, resolution, quality preset, DLSS/FSR upscaling and frame generation. - [Mouse Sensitivity Converter between Games](https://mathva.com/gaming/mouse-sensitivity-converter-between-games.md): Convert mouse sensitivity between CS2, Valorant, Apex Legends, Overwatch 2, Call of Duty and Destiny 2, with cm/360° and eDPI. - [DPI to eDPI Calculator](https://mathva.com/gaming/dpi-to-edpi-calculator.md): Calculate eDPI (effective DPI) from mouse DPI and in-game sensitivity, with cm/360° and how you compare with pro players in your game. - [XP to Next Level Calculator](https://mathva.com/gaming/xp-to-next-level-calculator.md): Calculate how much XP, how many matches and how many hours you need to reach the next level or a target level, with linear, exponential or custom XP curves. - [Loot Drop Probability Calculator](https://mathva.com/gaming/loot-drop-probability-calculator.md): Calculate loot drop odds: the chance of getting a rare drop within a number of kills or runs, expected drops, and attempts needed for 50%, 90% and 99%. - [Gacha Pull Probability Calculator](https://mathva.com/gaming/gacha-pull-probability-calculator.md): Calculate gacha pull odds for Genshin Impact, Honkai: Star Rail and similar games — chance of the featured 5★ with soft pity, hard pity and 50/50 guarantee. - [Game Completion Time Estimator](https://mathva.com/gaming/game-completion-time-estimator.md): Estimate how long it will take to beat a game or your whole backlog from story length, play style (main, extras, completionist) and weekly play time. - [Rank Progression Calculator](https://mathva.com/gaming/rank-progression-calculator.md): Calculate how many ranked games and hours it takes to climb from your current MMR, LP or SR to a target, based on win rate and rating gains and losses. - [DPS Calculator](https://mathva.com/gaming/dps-calculator.md): Calculate weapon or character DPS, sustained DPS with reloads, time to kill and hits to kill from damage, fire rate, accuracy, crits and armor. - [Character Build Stat Optimizer](https://mathva.com/gaming/character-build-stat-optimizer.md): Optimize character build stats: find the best split of substat rolls between ATK%, crit rate and crit damage to maximize average damage in RPG and gacha games. - [Speedrun Split Timer](https://mathva.com/gaming/speedrun-split-timer.md): Free online speedrun split timer: time each segment, compare live against your personal best, and see sum of best and possible time save. - [Steam Library Value Calculator](https://mathva.com/gaming/steam-library-value-calculator.md): Calculate your Steam library value — total spent, current store value, savings from sales, cost per hour played and your unplayed “pile of shame.” - [Game Key Price Comparison](https://mathva.com/gaming/game-key-price-comparison.md): Compare game key prices across stores including fees and tax, find the best authorized deal and see how gray-market sellers compare. - [Ping and Latency Explainer](https://mathva.com/gaming/ping-and-latency-explainer.md): Understand ping, jitter and packet loss for gaming: connection rating by game type, delay in frames, and how far the server can be. - [Download Time Estimator](https://mathva.com/gaming/download-time-estimator.md): Estimate how long a game, update or file will take to download at your internet speed in Mbps, MB/s or Gbps, including real-world overhead. - [Console Storage Planner](https://mathva.com/gaming/console-storage-planner.md): Plan console storage for PS5, PS5 Pro, Xbox Series X|S, Switch 2 and Steam Deck: see used and free space, how many more games fit and when to upgrade. - [Twitch Bits to Dollars Converter](https://mathva.com/gaming/twitch-bits-to-dollars-converter.md): Convert Twitch bits to dollars: how much streamers earn from cheers and roughly how much viewers pay for bits bundles. - [Esports Prize Split Calculator](https://mathva.com/gaming/esports-prize-split-calculator.md): Split an esports prize pool by placement and calculate each team’s and player’s share after organization cuts and tax withholding. ## Sports & Fantasy Golf handicap, Elo, batting average, passer rating, brackets and fantasy tools. - [Golf Handicap Calculator](https://mathva.com/sports/golf-handicap-calculator.md): Calculate your golf Handicap Index using the World Handicap System from recent scores, course ratings and slope, plus course and playing handicap. - [Fantasy Football Trade Value Calculator](https://mathva.com/sports/fantasy-football-trade-value-calculator.md): Fantasy football trade analyzer: compare player values by position and rank for PPR, half-PPR or standard, 1-QB or superflex leagues, with a 2-for-1 adjustment. - [Fantasy Draft Order Randomizer](https://mathva.com/sports/fantasy-draft-order-randomizer.md): Randomize your fantasy draft order fairly for snake or linear drafts, with a pick-by-pick board you can share with your league. - [League Scoring Calculator](https://mathva.com/sports/league-scoring-calculator.md): Calculate fantasy football points for any stat line in PPR, half-PPR and standard scoring, with 4- or 6-point passing touchdowns. - [Golf Scorecard Calculator](https://mathva.com/sports/golf-scorecard-calculator.md): Golf scorecard calculator: total score to par, front and back nine, birdies and bogeys, putts per hole, greens in regulation and fairways hit. - [Tennis Rating Calculator](https://mathva.com/sports/tennis-rating-calculator.md): Estimate your tennis NTRP rating (and approximate UTR) from a quick self-assessment of serve, groundstrokes, net play and match strategy. - [Bowling Score Calculator](https://mathva.com/sports/bowling-score-calculator.md): Bowling score calculator: enter strikes, spares and misses frame by frame to get the running total, final score and strike and spare counts. - [Chess Elo Calculator](https://mathva.com/sports/chess-elo-calculator.md): Chess Elo rating calculator: rating change after one or more games, expected score, new rating and tournament performance rating using FIDE K-factors. - [Batting Average Calculator](https://mathva.com/sports/batting-average-calculator.md): Calculate batting average, OBP, slugging percentage, OPS, ISO and BABIP from a baseball or softball hitter’s stats. - [ERA Calculator](https://mathva.com/sports/era-calculator.md): Calculate a pitcher’s ERA, WHIP, FIP, K/9, BB/9 and K/BB from earned runs, innings pitched, hits, walks, strikeouts and home runs. - [Passer Rating Calculator](https://mathva.com/sports/passer-rating-calculator.md): Calculate NFL passer rating (0–158.3) and NCAA passing efficiency from completions, attempts, yards, touchdowns and interceptions. - [Points per Game Calculator](https://mathva.com/sports/points-per-game-calculator.md): Calculate points, rebounds and assists per game, per-36-minute stats and projected season totals for basketball or any sport. - [Playoff Seeding Scenario Tool](https://mathva.com/sports/playoff-seeding-scenario-tool.md): Playoff picture calculator: current seeds, clinched and eliminated teams, magic numbers and elimination numbers from standings and games remaining. - [Tournament Bracket Generator](https://mathva.com/sports/tournament-bracket-generator.md): Generate a single-elimination tournament bracket for any number of teams or players, with standard seeding or a random draw and automatic byes. - [Round Robin Schedule Generator](https://mathva.com/sports/round-robin-schedule-generator.md): Generate a round-robin schedule where every team plays every other team — single or double round robin, with byes, home/away and dates. - [Random Team Splitter](https://mathva.com/sports/random-team-splitter.md): Split players into fair, balanced teams by skill rating for pickup games, PE classes and leagues, with equal team sizes and a reshuffle button. - [Race Handicap Calculator](https://mathva.com/sports/race-handicap-calculator.md): Set start times for a handicap race so runners of different abilities finish together, using predicted times from each runner’s recent race. - [Swim Time Converter](https://mathva.com/sports/swim-time-converter.md): Convert swim times between short course yards (SCY), short course meters (SCM) and long course meters (LCM) by stroke and distance. - [Track Split Calculator](https://mathva.com/sports/track-split-calculator.md): Track split calculator: lap-by-lap 400 m, 200 m and 100 m splits for your goal time in the 800, 1500, mile, 3000, 5000 and 10,000 meters. - [Team Budget Splitter](https://mathva.com/sports/team-budget-splitter.md): Split sports team costs fairly per player — registration, referees, uniforms and tournaments — after sponsors and fundraising, with sibling discounts and scholarships. ## Fashion & Sizing Clothing, shoe, ring and bra sizes, sewing and knitting math, jewelry value. - [Clothing Size Converter US/UK/EU](https://mathva.com/fashion/clothing-size-converter-us-uk-eu.md): Convert clothing sizes between US, UK, EU, France, Italy, Japan and letter sizes for women’s dresses and tops, men’s shirts, suits and pants. - [Shoe Size Converter](https://mathva.com/fashion/shoe-size-converter.md): Convert shoe sizes between US, UK, EU and foot length in cm or inches for men and women, including Mondopoint and men’s-to-women’s conversion. - [Ring Size Calculator](https://mathva.com/fashion/ring-size-calculator.md): Find your ring size from finger circumference, ring diameter or US size, and convert between US, UK, EU, Japanese and Swiss ring sizes. - [Bra Size Calculator](https://mathva.com/fashion/bra-size-calculator.md): Calculate your bra size from underbust and bust measurements, with US, UK, EU, French and Australian sizes and sister sizes. - [Hat Size Converter](https://mathva.com/fashion/hat-size-converter.md): Convert head circumference into hat sizes: US fitted fractions, UK, EU and S/M/L/XL, with a full hat size chart. - [Suit and Jacket Size Calculator](https://mathva.com/fashion/suit-and-jacket-size-calculator.md): Find your suit jacket size (e.g., 40R) from chest measurement and height, with trouser size, drop and EU/UK equivalents. - [Jeans Size Finder](https://mathva.com/fashion/jeans-size-finder.md): Find your jeans size from waist, hip and inseam measurements — men’s waist × length and women’s US and 24–34 waist sizes, with fit tips. - [Fabric Yardage Calculator](https://mathva.com/fashion/fabric-yardage-calculator.md): Calculate fabric yardage for a sewing project from pattern piece sizes, fabric width, seam allowance, pattern repeat and a shrinkage buffer. - [Knitting Yarn Calculator](https://mathva.com/fashion/knitting-yarn-calculator.md): Estimate how much yarn to buy for knitting or crochet — sweaters, hats, scarves, socks, blankets — by yarn weight and size, or from your gauge swatch. - [Crochet Gauge Calculator](https://mathva.com/fashion/crochet-gauge-calculator.md): Compare your crochet or knitting gauge with the pattern: see how much bigger or smaller your project will be and how to fix it with hook size or stitch count. - [Sewing Pattern Scaler](https://mathva.com/fashion/sewing-pattern-scaler.md): Scale and grade a sewing pattern to your measurements: bust, waist and hip changes per side seam, blending between sizes and print scale correction. - [Quilt Binding Calculator](https://mathva.com/fashion/quilt-binding-calculator.md): Calculate quilt binding: how many strips to cut and how much fabric to buy from quilt size, strip width and fabric width, straight grain or bias. - [Curtain Fabric Calculator](https://mathva.com/fashion/curtain-fabric-calculator.md): Calculate curtain fabric yardage from rod width, drop, heading fullness, panels, fabric width, hems and pattern repeat. - [Gold Jewelry Value Calculator](https://mathva.com/fashion/gold-jewelry-value-calculator.md): Calculate the melt value of gold jewelry from weight (grams, pennyweight or troy ounces), karat and today’s gold spot price, plus typical buyer offers. - [Diamond Price Estimator](https://mathva.com/fashion/diamond-price-estimator.md): Estimate diamond prices by carat, cut, color, clarity and shape for natural and lab-grown diamonds, with price per carat and money-saving tips. - [Watch Case Size for Wrist Calculator](https://mathva.com/fashion/watch-case-size-for-wrist-calculator.md): Find the right watch case size for your wrist: ideal diameter by style and look, maximum lug-to-lug length and strap length. - [Color Season Analyzer Quiz](https://mathva.com/fashion/color-season-analyzer-quiz.md): Take a quick color season quiz — undertone, contrast, hair and eyes — to find whether you’re a Spring, Summer, Autumn or Winter, with your best color palette. - [Capsule Wardrobe Planner](https://mathva.com/fashion/capsule-wardrobe-planner.md): Plan a capsule wardrobe: how many tops, bottoms, dresses, layers, shoes and accessories to own for your lifestyle and season, and how many outfits they make. - [Laundry Detergent Dose Calculator](https://mathva.com/fashion/laundry-detergent-dose-calculator.md): Find the right laundry detergent dose for liquid, powder, pods or sheets by load size, water hardness and how dirty clothes are, plus cost per load. - [Cost per Wear Calculator](https://mathva.com/fashion/cost-per-wear-calculator.md): Calculate cost per wear for clothes, shoes and accessories and compare a quality piece with a cheaper alternative over its lifespan. ## Photography & Video Depth of field, exposure, golden hour, astrophotography, bitrate and pricing. - [Image Resizer and Compressor](https://mathva.com/photography/image-resizer-and-compressor.md): Free image resizer and compressor: shrink JPG, PNG and WebP images by width, height and quality — processed privately in your browser, nothing uploaded. - [Depth of Field Calculator](https://mathva.com/photography/depth-of-field-calculator.md): Depth of field calculator: near and far limits of sharp focus, total DOF and hyperfocal distance for any focal length, aperture, distance and sensor size. - [Hyperfocal Distance Calculator](https://mathva.com/photography/hyperfocal-distance-calculator.md): Calculate hyperfocal distance for landscape photography — where to focus so everything from half that distance to infinity is sharp — by lens, aperture and sensor. - [Field of View Calculator](https://mathva.com/photography/field-of-view-calculator.md): Calculate a lens’s horizontal, vertical and diagonal field of view and how much scene it covers at a distance, for any sensor size. - [Exposure Triangle Calculator](https://mathva.com/photography/exposure-triangle-calculator.md): Exposure triangle calculator: change aperture, shutter speed or ISO and get the equivalent setting that keeps the same exposure, with EV and stops. - [ND Filter Exposure Calculator](https://mathva.com/photography/nd-filter-exposure-calculator.md): Calculate long-exposure shutter speed with ND filters (ND2 to ND32768, or any number of stops) from your metered exposure. - [Golden Hour and Blue Hour Calculator](https://mathva.com/photography/golden-hour-and-blue-hour-calculator.md): Find golden hour and blue hour times for photography at any city or GPS location and date, plus sunrise, sunset and solar noon. - [Star Trail Exposure Calculator](https://mathva.com/photography/star-trail-exposure-calculator.md): Plan star trail photography: how many frames to shoot, trail arc length, storage and battery needs from total time, exposure length and lens. - [500 Rule Astrophotography Calculator](https://mathva.com/photography/500-rule-astrophotography-calculator.md): Calculate the maximum shutter speed for sharp stars with the 500 rule, 300 rule and more accurate NPF rule for your lens, aperture and sensor. - [Crop Factor Calculator](https://mathva.com/photography/crop-factor-calculator.md): Calculate sensor crop factor and full-frame equivalent focal length and aperture for APS-C, Micro Four Thirds, 1-inch, phone and medium format cameras. - [Print Size and DPI Calculator](https://mathva.com/photography/print-size-and-dpi-calculator.md): Calculate the maximum print size for a photo at 300, 240 or 150 DPI, or how many pixels a print needs — with viewing-distance quality guidance. - [Video Bitrate Calculator](https://mathva.com/photography/video-bitrate-calculator.md): Find the right video bitrate for YouTube uploads, live streaming or editing masters by resolution, frame rate and codec — with file size per minute. - [Shoot Storage Requirement Calculator](https://mathva.com/photography/shoot-storage-requirement-calculator.md): Estimate storage for a photo or video shoot — RAW files, JPEGs and video bitrate — with memory cards needed and backup capacity. - [Timelapse Interval Calculator](https://mathva.com/photography/timelapse-interval-calculator.md): Timelapse calculator: shooting interval, number of frames, speed-up and storage from event duration, clip length and playback frame rate. - [Slow Motion Frame Rate Calculator](https://mathva.com/photography/slow-motion-frame-rate-calculator.md): Slow motion calculator: playback speed and slow-down factor from recording and timeline frame rates, clip length, and the fps needed for a target slow-mo. - [Green Screen Lighting Calculator](https://mathva.com/photography/green-screen-lighting-calculator.md): Plan green screen lighting: how many lights for the backdrop, where to place them, subject distance and green spill risk for clean chroma keying. - [Photography Pricing Calculator](https://mathva.com/photography/photography-pricing-calculator.md): Photography pricing calculator: what to charge per shoot to cover your salary, taxes, business costs and gear, with your effective hourly rate. - [Second Shooter Cost Calculator](https://mathva.com/photography/second-shooter-cost-calculator.md): Calculate the true cost of hiring a second shooter — hourly or flat rate, travel, meals, delivery and your extra editing time — as a share of your package. - [Drone Flight Time Calculator](https://mathva.com/photography/drone-flight-time-calculator.md): Estimate drone flight time from battery capacity, cell count, weight, hover efficiency and wind, plus batteries needed and airline battery rules. - [Audio File Size Calculator](https://mathva.com/photography/audio-file-size-calculator.md): Calculate audio file size for WAV, AIFF, FLAC, MP3, AAC and Opus from sample rate, bit depth, channels, bitrate and duration. - [Podcast Episode Length Planner](https://mathva.com/photography/podcast-episode-length-planner.md): Plan podcast episode length: segment timings, ad breaks, running order timestamps, words to script and how you compare with your target runtime. ## Environment & Sustainability Carbon footprint, flight and car emissions, diet impact, water use and recycling. - [Carbon Footprint Calculator](https://mathva.com/environment/carbon-footprint-calculator.md): Calculate your personal carbon footprint in tonnes of CO₂ per year from home energy, driving, flights, diet, shopping and waste, compared with national averages. - [Heat Index Calculator](https://mathva.com/environment/heat-index-calculator.md): Heat index calculator: find the “feels like” temperature from air temperature and humidity in °F or °C, with National Weather Service heat risk levels. - [Wind Chill Calculator](https://mathva.com/environment/wind-chill-calculator.md): Wind chill calculator: see how cold it feels from temperature and wind speed (°F/mph or °C/km/h) and how fast frostbite can occur. - [Dew Point Calculator](https://mathva.com/environment/dew-point-calculator.md): Dew point calculator: find the dew point from temperature and relative humidity in °F or °C, with comfort level and condensation risk. - [Flight Emissions Calculator](https://mathva.com/environment/flight-emissions-calculator.md): Calculate flight carbon emissions between cities by cabin class, round trip and passengers — including non-CO₂ warming effects — with car-mile and offset equivalents. - [Car Emissions Calculator](https://mathva.com/environment/car-emissions-calculator.md): Calculate your car’s CO₂ emissions per year and per mile for gasoline, diesel, hybrid or electric vehicles, and compare with an EV on your grid. - [Diet Carbon Footprint Calculator](https://mathva.com/environment/diet-carbon-footprint-calculator.md): Calculate the carbon footprint of your diet from weekly servings of beef, pork, chicken, fish, dairy, eggs, rice and plant proteins, with swap savings. - [Home Carbon Footprint Calculator](https://mathva.com/environment/home-carbon-footprint-calculator.md): Calculate your home’s carbon footprint from electricity, natural gas, propane and heating oil, per person, with the CO₂ savings of common upgrades. - [Recycling Savings Calculator](https://mathva.com/environment/recycling-savings-calculator.md): Calculate how much CO₂ your household saves by recycling paper, plastic, aluminum, glass and steel and composting food scraps, with car-mile equivalents. - [Household Water Usage Calculator](https://mathva.com/environment/household-water-usage-calculator.md): Calculate household water usage per day and per person from showers, baths, toilets, faucets, dishwasher, laundry and outdoor watering, with savings tips. - [Composting Ratio Calculator](https://mathva.com/environment/composting-ratio-calculator.md): Calculate your compost pile’s carbon-to-nitrogen (C:N) ratio from greens and browns like grass, food scraps, leaves and cardboard, and how to balance it. - [Tree Planting Offset Calculator](https://mathva.com/environment/tree-planting-offset-calculator.md): Calculate how many trees or acres of forest it takes to offset your carbon emissions, and compare the cost of tree planting with verified carbon offsets. - [Plastic Usage Tracker](https://mathva.com/environment/plastic-usage-tracker.md): Track your single-use plastic: bottles, cups, bags, takeout containers and wrappers per year in items and kilograms, with the impact of reusable swaps. ## Fun, Viral & Quizzes Random pickers, name generators, quizzes, compatibility and “how do you compare” tools. - [Random Number Generator](https://mathva.com/fun/random-number-generator.md): Random number generator: pick one or many random numbers in any range, with no duplicates, sorting and decimals — generated securely in your browser. - [Life Expectancy Calculator](https://mathva.com/fun/life-expectancy-calculator.md): Life expectancy calculator: estimate how long you might live based on age, sex and lifestyle — smoking, exercise, BMI, alcohol, diet, sleep and social ties. - [Love Compatibility Calculator](https://mathva.com/fun/love-compatibility-calculator.md): Calculate love compatibility between two names and birthdays — a fun love score, zodiac match and date idea to share with your crush or partner. - [Name Compatibility Calculator](https://mathva.com/fun/name-compatibility-calculator.md): Name compatibility calculator: play the classic FLAMES game (Friends, Lovers, Affectionate, Marriage, Enemies, Siblings) plus numerology name harmony. - [Random Name Picker Wheel](https://mathva.com/fun/random-name-picker-wheel.md): Spin a random name picker wheel to choose a winner, student or team fairly — add names, pick one or several winners and spin again. - [Coin Flip and Dice Roller](https://mathva.com/fun/coin-flip-and-dice-roller.md): Flip a coin or roll dice online — d4, d6, d8, d10, d12, d20 and d100 — with multiple dice, modifiers and totals, using fair random results. - [Team Randomizer](https://mathva.com/fun/team-randomizer.md): Randomly split a list of names into teams or groups — by number of teams or people per team — for classrooms, games and work events. - [Secret Santa Generator](https://mathva.com/fun/secret-santa-generator.md): Free Secret Santa generator: draw names for a gift exchange with exclusions for couples or roommates, a budget and ready-to-send messages. - [Decision Maker Wheel](https://mathva.com/fun/decision-maker-wheel.md): Spin a decision maker wheel to choose between options — what to eat, where to go, what to do — with optional weights for favorite choices. - [Bucket List Generator](https://mathva.com/fun/bucket-list-generator.md): Generate bucket list ideas for travel, adventure, learning, creativity, giving back and food — shuffle for new inspiration and copy your list. - [Baby Name Generator](https://mathva.com/fun/baby-name-generator.md): Baby name generator: discover girl, boy and gender-neutral names by style — classic, modern, nature, royal or unique — with meanings and origins. - [Username Generator](https://mathva.com/fun/username-generator.md): Username generator: create unique gamer tags, professional handles and cute or aesthetic usernames from words you like, for games and social media. - [Band Name Generator](https://mathva.com/fun/band-name-generator.md): Band name generator: get creative band names for rock, indie, metal, pop, punk, jazz, electronic, country and hip-hop, optionally including your own word. - [Business Name Generator](https://mathva.com/fun/business-name-generator.md): Business name generator: brainstorm catchy, classic, playful or luxury business names by industry and keyword, with matching domain ideas. - [Domain Name Idea Generator](https://mathva.com/fun/domain-name-idea-generator.md): Domain name idea generator: combine keywords with prefixes and suffixes into short, brandable domain names and check .com availability. - [Nickname Generator](https://mathva.com/fun/nickname-generator.md): Nickname generator: find cute, cool, funny and classic nicknames for any first name — for friends, partners, kids and gamer tags. - [Fantasy Character Name Generator](https://mathva.com/fun/fantasy-character-name-generator.md): Fantasy name generator for elves, dwarves, humans, orcs, halflings and dragons — unique character names with surnames and titles for D&D, games and stories. - [What Should I Watch Tonight Picker](https://mathva.com/fun/what-should-i-watch-tonight-picker.md): Can’t decide what to watch? Get a random movie or TV show pick by mood, time available and family-friendliness from a list of acclaimed titles. - [Would You Rather Generator](https://mathva.com/fun/would-you-rather-generator.md): Random “would you rather” questions — funny, deep, travel, food and work — for parties, icebreakers, road trips and family game night. - [Truth or Dare Generator](https://mathva.com/fun/truth-or-dare-generator.md): Truth or dare generator with clean questions and safe, silly dares for kids, families, teens and adults — random picks for parties and sleepovers. - [Trivia Quiz Generator](https://mathva.com/fun/trivia-quiz-generator.md): Free online trivia quiz with multiple-choice questions on general knowledge, science, geography, history, sports and entertainment — answers included. - [Personality Type Quiz](https://mathva.com/fun/personality-type-quiz.md): Take a quick free personality type quiz — 12 questions across introversion/extraversion, sensing/intuition, thinking/feeling and judging/perceiving. - [Career Aptitude Quiz](https://mathva.com/fun/career-aptitude-quiz.md): Free career aptitude quiz based on the Holland RIASEC model — rate 12 activities to find your interest code and matching career ideas. - [Which City Should I Live in Quiz](https://mathva.com/fun/which-city-should-i-live-in-quiz.md): Which city should I live in? Take the quiz — match your budget, weather, city size, career and lifestyle to find your best-fit U.S. city. - [Dog Breed Matcher Quiz](https://mathva.com/fun/dog-breed-matcher-quiz.md): Dog breed selector quiz: match your home, activity level, kids, shedding and grooming preferences to find the best dog breeds for your lifestyle. - [Zodiac Compatibility Calculator](https://mathva.com/fun/zodiac-compatibility-calculator.md): Zodiac compatibility calculator: check love compatibility between any two star signs with elements, strengths and challenges — Aries to Pisces. - [How Rich Are You Globally Calculator](https://mathva.com/fun/how-rich-are-you-globally-calculator.md): How rich am I globally? Compare your household income with the world population, adjusted for household size and local prices, and see your global percentile. - [Salary Percentile Calculator](https://mathva.com/fun/salary-percentile-calculator.md): Salary percentile calculator: see how your income compares with U.S. full-time workers or all earners, overall or by age group, with median and top 1% cutoffs. - [Lifetime Social Media Time Calculator](https://mathva.com/fun/lifetime-social-media-time-calculator.md): How much of your life will you spend on social media? Calculate lifetime hours and years scrolling, plus what you could do with the time you win back. - [Screen Time Cost Calculator](https://mathva.com/fun/screen-time-cost-calculator.md): Screen time cost calculator: see the hours, days and dollar value of your daily screen time, and what reclaiming an hour a day could be worth over years. - [Naam Jap Mantra Counter](https://mathva.com/fun/naam-jap-mantra-counter.md): Naam jap counter online: count Ram, Radhe Radhe, Om Namah Shivaya, Gayatri and other mantras with a 108-bead mala tracker, daily goal and saved totals. ## Optional - [Download the app](https://mathva.com/app): install Mathva as an offline app - [What's new](https://mathva.com/whats-new): changelog - [Contact](https://mathva.com/contact): hello@mathva.com