Conversion Calculator

Convert between common units of length, area, volume, weight, and temperature.

How conversions work

Every unit within a category is defined relative to a common base unit (meters for length, liters for volume, kilograms for weight, and so on). Converting from one unit to another is a two-step process: convert the input into the base unit, then convert the base unit into the target unit. Temperature is the exception, since Celsius, Fahrenheit, and Kelvin scales don't share a zero point.

Precision

Conversion factors used here (like 1 mile = 1,609.344 meters, or 1 pound = 0.45359237 kilograms) are the internationally defined exact values, not rounded approximations.

US volume units (gallon, quart, pint, cup, fluid ounce) use the US customary definitions, which differ slightly from the UK imperial system.

Common questions

Why does switching categories reset the units?

Each category has its own set of compatible units — length and weight, for example, can't be converted into each other, so the "From" and "To" lists update to match the category you pick.

Can I convert between metric and imperial units?

Yes — that's one of the most common uses of this calculator. Pick any "From" unit and any "To" unit within the same category, metric or imperial.

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