Free calculators & unit converters
Fast, accurate online calculators for percentages, BMI, mortgages, loans, salaries, calories and more — plus converters for length, weight, temperature, area, volume, speed, data and time.
Calculators
Everyday
Percentage Calculator
Free percentage calculator: find what X% of a number is, what one number is as a percent of another, and percentage increase or decrease.
EverydayAge Calculator
Free age calculator: find your exact age in years, months and days, plus total days, weeks and months from any date of birth.
EverydayDate Difference Calculator
Free date difference calculator: count the days, weeks, months and years between any two dates, with a full breakdown.
EverydayTip Calculator
Free tip calculator: split a restaurant bill, calculate the tip amount and see the total per person in seconds.
EverydayDiscount Calculator
Free discount calculator: find the final price after a percentage discount and see exactly how much you save.
EverydayFuel Cost Calculator
Free fuel cost calculator: estimate trip fuel usage and total cost in US (miles/MPG) or metric (km/km/L) units.
EverydayTime Zone Converter
Free time zone converter: find the time in another city or time zone instantly, with world clock support.
Finance
Mortgage Calculator
Free mortgage calculator: estimate your monthly mortgage payment, total interest and total repayment for any loan amount, rate and term.
FinanceLoan Calculator
Free loan calculator: estimate monthly payments, total interest and total repayment for personal, auto and other installment loans.
FinanceCompound Interest Calculator
Free compound interest calculator: project investment growth with monthly contributions and see total interest earned over time.
FinanceSalary to Hourly Calculator
Free salary to hourly calculator: convert an annual salary to an hourly, daily, weekly and monthly rate based on your work hours.
FinanceRetirement Calculator
Free retirement calculator: estimate how much your savings will grow by retirement age with annual contributions and compound returns.
FinanceCurrency Converter
Free currency converter with live exchange rates — convert between USD, TZS and 100+ other currencies.
Health
BMI Calculator
Free BMI calculator: check your body mass index in metric or imperial units and see which weight category you fall into.
HealthCalorie Calculator
Free calorie calculator: estimate your BMR and daily TDEE (maintenance calories) using the Mifflin-St Jeor equation.
HealthPregnancy Due Date Calculator
Free pregnancy due date calculator: estimate your baby's due date and conception date from the first day of your last period.
HealthBody Fat Calculator
Free body fat percentage calculator using the US Navy method — estimate body fat from height, neck, waist and hip measurements.
Unit converters
Length Converter
Convert between metric and imperial length units — millimeters, centimeters, meters, kilometers, inches, feet, yards, miles and nautical miles.
Weight & Mass Converter
Convert between metric and imperial weight and mass units — milligrams, grams, kilograms, tonnes, ounces, pounds and stones.
Temperature Converter
Convert between Celsius, Fahrenheit and Kelvin. Temperature is an affine scale, so conversions use both a multiplier and an offset.
Area Converter
Convert between metric and imperial area units — square meters, square kilometers, hectares, acres, square feet, square yards and more.
Volume Converter
Convert between metric and imperial volume units — milliliters, liters, cubic meters, gallons, quarts, pints, fluid ounces and cups.
Speed Converter
Convert between speed units — meters per second, kilometers per hour, miles per hour, knots and feet per second.
Data Storage Converter
Convert between digital storage units — bits, bytes, kilobytes, megabytes, gigabytes, terabytes and petabytes. Uses binary (1,024) multiples.
Time Converter
Convert between time units — milliseconds, seconds, minutes, hours, days, weeks, months (average) and years (average).