Calculators that show their work
Most calculators hand you a number and stop. These give you the formula, the month-by-month breakdown, and the assumptions behind the result - so you can check the answer rather than trust it.
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Most used
- Mortgage CalculatorEstimate your monthly mortgage payment - including taxes, insurance, and PMI - and see exactly how much interest you'll pay over the life of the loan.Open
- BMI CalculatorCalculate your body mass index in metric or imperial units, and see where it falls on the standard scale.Open
- Percentage CalculatorSolve every common percentage question - what is X% of Y, X is what percent of Y, and the percentage change between two numbers.Open
- Loan CalculatorCalculate the monthly payment, total interest, and payoff date on any fixed-rate loan - then see the full schedule behind the number.Open
- Calorie CalculatorFind your daily calorie needs from your BMR and activity level, with targets for losing, maintaining, or gaining weight.Open
- Age CalculatorWork out an exact age in years, months, and days from any date of birth - plus total days lived and the countdown to the next birthday.Open
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24 calculators match
Finance
View all- Mortgage CalculatorEstimate your monthly mortgage payment - including taxes, insurance, and PMI - and see exactly how much interest you'll pay over the life of the loan.
- Loan CalculatorCalculate the monthly payment, total interest, and payoff date on any fixed-rate loan - then see the full schedule behind the number.
- Auto Loan CalculatorWork out your real monthly car payment with sales tax, trade-in value, and fees included - not just the sticker price.
- Amortization CalculatorGenerate a complete payment-by-payment schedule for any loan, and see exactly how each payment splits between principal and interest.
- Paycheck CalculatorSee your real take-home pay after federal tax, Social Security, Medicare, state tax, and retirement contributions - for 2025.
- Compound Interest CalculatorSee how savings grow when interest earns interest - with monthly contributions and a year-by-year breakdown of the balance.
- Retirement CalculatorProject what your 401(k) and savings will be worth at retirement, and see how long that balance actually lasts.
- Credit Card Payoff CalculatorFind out how long your credit card balance takes to clear, what the interest costs, and how much faster a bigger payment gets you there.
- Home Affordability CalculatorFind the home price your income actually supports, using the debt-to-income limits lenders apply - and see which limit is binding.
Health
View all- BMI CalculatorCalculate your body mass index in metric or imperial units, and see where it falls on the standard scale.
- Calorie CalculatorFind your daily calorie needs from your BMR and activity level, with targets for losing, maintaining, or gaining weight.
- Due Date CalculatorEstimate your due date from your last period, conception date, or a known due date - and see exactly how far along you are.
Everyday
View all- Percentage CalculatorSolve every common percentage question - what is X% of Y, X is what percent of Y, and the percentage change between two numbers.
- Age CalculatorWork out an exact age in years, months, and days from any date of birth - plus total days lived and the countdown to the next birthday.
- Tip CalculatorCalculate the tip and split the check between any number of people, with a rounding option and a US tipping reference.
- Time Zone ConverterConvert a time across cities and plan meetings that land in working hours everywhere - with daylight saving handled automatically.
Converters
View all- CM to Inches ConverterConvert centimeters to inches instantly, with a reference table for the sizes you look up most.
- KG to LBS ConverterConvert kilograms to pounds instantly, with a reference table covering everyday body and package weights.
- Celsius to Fahrenheit ConverterConvert °C to °F instantly, with a reference table covering weather, body temperature, and cooking.
- MM to Inches ConverterConvert millimeters to inches instantly, with a reference table for common hardware and screen sizes.
- KM to Miles ConverterConvert kilometers to miles instantly, with a reference table covering race distances and road trips.
- Meters to Feet ConverterConvert meters to feet instantly, with a reference table for heights, rooms, and elevations.
- Ounces to Grams ConverterConvert ounces to grams instantly, with a reference table sized for recipes and postage.
- MPH to KM/H ConverterConvert miles per hour to kilometers per hour instantly, with a reference table of common speed limits.