Calculators

Calculate exact age in years, months, and days from a birth date, with leap-year accuracy.

Work out percentages, percentage of a number, and what percent one value is of another.

Calculate percentage increase or decrease between an old and a new value.

Simplify ratios and solve proportions to find a missing value in A:B = C:D.

Find the mean, median, mode, sum, and range of a list of numbers.

A full scientific calculator with trig, logarithms, powers, roots, and operator precedence.

Calculate Body Mass Index in metric or imperial units, with a WHO category.

Estimate basal metabolic rate and daily calorie needs using the Mifflin-St Jeor equation.

Calculate monthly loan EMI, total interest, and total payment from principal, rate, and tenure.

Calculate simple interest and maturity amount from principal, rate, and time.

Calculate compound interest and future value with adjustable compounding frequency.

Add or remove GST/VAT with inclusive, exclusive, and reverse calculation modes.

Calculate the sale price and amount saved from an original price and discount percentage.

Calculate profit or loss and margin percentage from cost price and selling price.

Convert between metres, kilometres, miles, feet, inches, yards, and more.

Convert between kilograms, grams, pounds, ounces, stones, and tonnes.

Convert between Celsius, Fahrenheit, and Kelvin with exact formulas.

Convert between square metres, square feet, acres, hectares, and more.

Convert between litres, millilitres, gallons, cups, pints, and cubic metres.

Convert between km/h, mph, m/s, knots, and feet per second.

Convert between bytes, KB, MB, GB, TB using binary or decimal units.

Convert between seconds, minutes, hours, days, weeks, and years.

Estimate months to pay off a credit card balance, total interest and a monthly schedule, or the payment for a target date.

Find the least common multiple and greatest common factor of two or more integers, with prime factorisations and steps.

Find the symmetric percentage difference between two values, with the absolute difference and average magnitude.

Add, subtract, multiply and divide fractions and mixed numbers, simplified exactly, with steps and a decimal value.

Find the radius, diameter, circumference and area of a circle from any one of them, with formulas and a diagram.

Calculate population or sample standard deviation, variance, mean, median, range and sum for a list of numbers.

Count the days between two dates, with weeks, calendar years, months and days, and total hours, minutes and seconds.

Work out the tip, tax, total and each person’s share of a bill, with rounding options and a fair split.

Estimate fuel used and trip cost from distance, fuel efficiency and price, in km/L, L/100 km or US and Imperial mpg.

Calculate a credit-weighted GPA on a 4.0 or 10-point scale, or with your own grade points, course by course.

Find your current weighted course grade from assessment scores and weights, and the score you need to reach a target.

Solve ax² + bx + c = 0 for real, repeated or complex roots, with the discriminant, exact forms, steps and a graph.

Add or subtract days, weeks, months or years from a date and get the result date, weekday and ISO date.

Count working days between two dates, or add and subtract business days, with custom weekends and holidays.

Estimate adult ideal-weight ranges from height with the Devine, Robinson, Miller and Hamwi formulas, in kg and lb.

Estimate adult body-fat percentage with the US Navy circumference method from height, neck, waist and hip measurements.

Estimate your one-rep max with the Epley, Brzycki and Lander formulas, plus a training-load table from 95% to 50%.

Estimate maximum heart rate and moderate and vigorous exercise ranges by age, with optional Karvonen ranges from resting heart rate.

Work out total invested, net gain or loss and simple return on investment (ROI) from cost, final value and fees.

Calculate compound annual growth rate between a beginning and ending value over years and months.

Estimate how long it takes to reach a savings goal, or the monthly amount needed by a chosen date, with optional growth.

Estimate an emergency fund target from essential monthly expenses and the number of months you want to cover.

Calculate your debt-to-income ratio from gross monthly income and recurring monthly debt payments.

Total your assets and liabilities to calculate net worth, with editable rows for each item.

Estimate adult BMR (Mifflin–St Jeor), maintenance calories by activity level and general planning estimates, in metric or imperial.

Split a daily calorie figure into protein, carbohydrate and fat calories and grams from percentages totalling 100%.

Estimate adult lean body mass and fat mass with the Boer formula from sex, height and weight, in kg and lb.

Calculate adult waist-to-height ratio and percentage from height and waist in metric or imperial units, with reference ranges.

Estimate a due date from the last menstrual period and cycle length, with gestational age and days remaining.

Plan bedtimes or wake-up times with 90-minute sleep cycles and a fall-asleep allowance, in 12- or 24-hour time.