Everyday math
in one place.
22 free calculators for money, health, dates and units. Type a value and get the answer instantly.
How it works
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Always free, no sign-up. U.S. units with a metric option.
Everything has
a color.
Calculators are grouped by color. Scroll and the cards stack up.
All calculators
Mortgage Calculator
Estimate your monthly mortgage payment with property tax, homeowners insurance, PMI and HOA dues, plus total interest and a yearly amortization table.
Loan Calculator
Calculate the monthly payment, total interest and payoff date for any fixed-rate loan, with an amortization schedule and extra payments.
CD Calculator
See how much a certificate of deposit earns by maturity, convert APY and APR, estimate tax on the interest and the cost of an early withdrawal.
Credit Card Payoff Calculator
Find how long it takes to pay off a credit card, the payment needed to be debt-free by a set date, and what paying only the minimum really costs.
Sales Tax Calculator
Add sales tax to a price, remove it from a total, or find the rate you paid. Includes 2026 statewide rates for all 50 states and D.C.
Amazon Fee Calculator
Work out Amazon referral fees, per-item and FBA fees, your payout, profit, margin and ROI, or find the price you need for a target profit.
Etsy Fee Calculator
See every Etsy fee on an order (listing, 6.5% transaction, payment processing, Offsite Ads), your payout and profit, or the price for a target profit.
Hourly to Salary Calculator
Convert an hourly wage to an annual salary or a salary to an hourly rate, with daily, weekly, biweekly, semimonthly and monthly pay.
Overtime Calculator
Calculate overtime pay at time and a half and double time under the federal 40-hour rule or California daily overtime, for hourly or salaried workers.
BMI Calculator
Calculate your body mass index from height and weight in feet, inches and pounds or metric units, with your healthy weight range.
Body Fat Calculator
Estimate your body fat percentage from height, neck, waist and hip measurements with the U.S. Navy method, plus fat mass and lean mass.
Calorie Calculator
Estimate how many calories you burn per day (BMR and TDEE) and how many to eat to lose, maintain or gain weight, using Mifflin-St Jeor.
Ovulation Calculator
Predict your ovulation day, fertile window and next period from the first day of your last period and your cycle length, for the next 6 cycles.
Due Date Calculator
Find your baby’s due date from your last period, conception date or IVF transfer, plus how many weeks pregnant you are and key milestones.
GPA Calculator
Calculate your GPA on the 4.0 scale from letter grades and credits, see weighted GPA with Honors and AP classes, and update your cumulative GPA.
Final Grade Calculator
Find the score you need on your final exam to get an A, B or C in the class, from your current grade and how much the final is worth.
Percentage Calculator
Find X% of a number, what percent one number is of another, the percent change between two values, or add and subtract a percentage.
Age Calculator
Calculate your exact age in years, months and days from your date of birth, plus total weeks and days lived and the countdown to your next birthday.
Number to Words Converter
Convert any number to words in U.S. English, write a check amount the right way (and 56/100 dollars) or spell out dollars and cents.
Length Converter
Convert inches to centimeters, feet to meters, miles to kilometers and more, with feet-and-inches output and a full conversion table.
Weight Converter
Convert pounds to kilograms, kilograms to pounds, ounces to grams and stones, with pounds-and-ounces output and handy charts.
Temperature Converter
Convert Fahrenheit to Celsius, Celsius to Fahrenheit and Kelvin instantly, with body temperature, cooking and weather charts.