Unit Converter

Convert between units across eight everyday categories: length, mass, temperature, data, speed, time, area, and volume. Pick a category, choose the units, and type a value to see the result instantly. Conversions use exact factors (the inch is precisely 25.4 mm, a US gallon is 3.785411784 L) and temperature handles the Celsius, Fahrenheit, and Kelvin offsets correctly.

Math

Convert between units of length, mass, temperature, data, speed, time, area, and volume. Pick a category, type a value, and the result updates as you go.

From

1000

1 Kilometer (km) = 1000 Meter (m)

What it converts

Eight categories cover the conversions people reach for most: length (meters, miles, feet, inches), mass (kilograms, pounds, ounces, stone), temperature (Celsius, Fahrenheit, Kelvin), data (bytes through terabytes, plus the binary KiB/MiB/GiB units), speed (m/s, km/h, mph, knots), time (milliseconds to weeks), area (square meters, acres, hectares), and volume (liters, gallons, cups, tablespoons).

How to use it

Choose a category, then pick the unit to convert from and the unit to convert to. Type a number in the From field and the result updates as you type. Use the swap button to flip the two units so you can convert the other way without re-picking them. Copy the result with one click.

Why the numbers are exact

Imperial and metric lengths use defined factors, so an inch is exactly 25.4 mm and a mile is 1609.344 m
Data sizes keep decimal (KB = 1000 bytes) and binary (KiB = 1024 bytes) units separate so you don't mix them up
Temperature uses real offset math, not a single multiplier, so 100°C correctly becomes 212°F
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