Unit Converter

Unit conversion shows up across almost every science and math class — converting a measurement in a physics problem, a recipe in a chemistry lab, or just checking whether a distance in miles matches one in kilometers. This tool covers four of the most common categories: length, weight, temperature, and volume, each with the units you're most likely to actually need.

Length, weight, and volume all convert the same way — multiplying by a fixed factor between two units of the same physical quantity, so 12 inches always converts to exactly 1 foot, no matter how many times you run it. Temperature is the one category that works differently: Celsius, Fahrenheit, and Kelvin don't share a common zero point, so converting between them uses dedicated formulas (for example, °F = °C × 9/5 + 32) rather than a simple multiplier.

Volume and weight use US customary units (US gallons, quarts, and the standard avoirdupois pound and ounce) — if you need UK/imperial equivalents, note that those use different gallon and pint sizes and won't match these numbers. For temperature, this tool won't accept a value below absolute zero (−273.15°C), since that's not physically possible regardless of which unit you enter it in.