Unit converters.
Turn one unit into another without the mental math.
Temperature Converter
Switch between Celsius, Fahrenheit, and Kelvin.
Weight Converter
Convert kilograms, grams, pounds, ounces and stones.
Length Converter
Convert metric lengths, inches, feet and miles.
Speed Converter
Convert metres per second, kilometres per hour, mph and knots.
Data Storage Converter
Compare bits, bytes, decimal storage units and binary storage units.
Number Base Converter
Convert signed whole numbers between bases 2 through 36 exactly.
Timezone Converter
Convert a date and time between world time zones.
Roman Numeral Converter
Convert between whole numbers and Roman numerals.
Volume Converter
Convert liters, milliliters, US and UK gallons, cups and fluid ounces.
Area Converter
Convert square meters, square feet, acres, hectares and square miles.
About unit converters
Unit conversions that come up when a recipe, a specification or a shipping form uses a system you do not think in: temperature, weight, length, speed, volume, area, data storage, and number bases between binary, octal, decimal and hexadecimal.
Each conversion shows the factor it applied, which makes the result checkable and occasionally catches the mistake that matters — confusing a kilobyte defined as 1000 bytes with one defined as 1024, or a US gallon with an imperial one. The colour converter works the same way across hex, RGB and HSL.