Calculators
Finance, taxes by country, math, geometry, dates. Every formula is documented and sourced.
HealthSee all 9
BMI calculatorTier 0Enter your height and weight to see your BMI, its category and the healthy weight range for your height.Due date calculatorTier 0Enter the first day of your last period and your usual cycle length.Calorie calculatorTier 0Enter your details and how active you are to estimate your daily calorie needs.Body fat calculatorTier 0Measure your neck and waist (and hips, for women) with a tape and enter them with your height.Ovulation calculatorTier 0Enter the first day of your last period and your average cycle length.BMR calculatorTier 0Enter your sex, age, height and weight to estimate the calories you burn at complete rest.Ideal weight calculatorTier 0Enter your sex and height to compare the classic ideal-weight formulas with the healthy BMI range.Pace calculatorTier 0Enter a distance and your time to get your pace and predicted race times.
FinanceSee all 38
Currency converterTier 1Convert dollars, euros, reais and 27 other currencies at the European Central Bank's official daily reference rates.Mortgage calculatorTier 0Enter the home price, down payment and rate to see the full monthly cost of a mortgage.Compound interestTier 0Project a balance from an initial deposit plus monthly contributions at a fixed annual rate, compounded annually to daily. Everything runs on this page.Car loan calculatorTier 0Enter the car price, what you put down and the loan terms to see your monthly payment.Loan calculatorTier 0Enter the amount, rate and term to see your payment and how the balance falls each year.Paycheck calculatorTier 0Enter your salary, pay frequency and filing status to see your net pay per paycheck.Amortization scheduleTier 0See exactly where each payment goes, month by month, until the balance reaches zero.Inflation calculatorTier 0Enter an amount, an average inflation rate and the number of years.
MathSee all 28
Random number generatorTier 0Pick a range and get truly unpredictable numbers for draws, games, samples and decisions.PercentageTier 0Three everyday percentage questions in one place: a percent of a number, one number as a percent of another, and the percent change from one value to another.Average calculatorTier 0Paste a list of numbers and get every common average at once.Fraction calculatorTier 0Type two fractions, mixed numbers or decimals and pick an operation.Square rootTier 0Enter a number and the root you want; whole numbers also get their simplified radical form.Circle areaTier 0Enter the radius, diameter, circumference or area to get all the others.Quadratic equation solverTier 0Enter a, b and c to find where the parabola crosses zero.Ratio calculatorTier 0Enter a ratio and a new value to scale it, and see the ratio in its simplest form.
Dates and time
Age calculatorTier 0Enter a date of birth to see the exact age today or on any other date.Date difference calculatorTier 0Pick a start and an end date to count the days between them.Hours calculatorTier 0Enter a start time, an end time and any unpaid break.Add to date calculatorTier 0Pick a date, choose add or subtract and enter an amount.Time card calculatorTier 0Enter one shift per line as start, end and unpaid break minutes, then your hourly rate.Week number calculatorTier 0Pick a date to see its ISO week number; today is selected by default.Business days calculatorTier 0Pick a start and an end date to count the weekdays between them.Day of the week calculatorTier 0Pick any date to see which weekday it falls on.
Everyday
Discount calculatorTier 0Enter the price and the discount to see what you pay and how much you save.GPA calculatorTier 0List your courses with a grade and credits, one per line.Grade calculatorTier 0Enter each graded item with its score and weight, plus the grade you are aiming for.Tip calculatorTier 0Enter the bill, choose a tip and split it between your group.Fuel cost calculatorTier 0Enter the distance, your car's fuel economy and the price of fuel.Electricity cost calculatorTier 0Enter the appliance's watts, how long it runs each day and your price per kWh.Unit price calculatorTier 0Enter the price and size of two options to see which costs less per unit.
Cooking
Electronics
Ohm's law calculatorTier 0Choose which two values you know and enter them to get the other two.Voltage divider calculatorTier 0Enter the input voltage and resistors, or a target output to find R2.LED resistor calculatorTier 0Enter the supply voltage, your LED's forward voltage and the current you want.