Convert between units of length, weight, temperature and more — instantly, on your device.
— Pick a category, choose the unit you're converting from and the unit you want, and the result updates as you type. Every calculation runs in your browser using precise conversion factors, so there is no lookup to a server and no delay. Linear units — length, weight, volume, area, speed and data — are converted through a common base unit, while temperature uses its own formulas because the scales have different zero points.
The converter handles length (from millimetres to miles), weight and mass (milligrams to stones), temperature (Celsius, Fahrenheit, Kelvin), volume (millilitres to US gallons, including cooking measures), area (square metres to acres), speed (m/s, km/h, mph, knots) and digital storage. For data, both decimal units (KB, MB, GB — powers of 1000) and binary units (KiB, MiB, GiB — powers of 1024) are included, so you can convert correctly depending on which convention a device or file size uses.
Results are shown to several significant figures and trimmed of trailing zeros for readability. Very large or very small results switch to scientific notation. Conversion factors follow standard definitions, so the output is accurate for everyday and most technical needs; for legal or scientific work requiring certified precision, always confirm against an authoritative reference.
A kilobyte (KB) is 1,000 bytes; a kibibyte (KiB) is 1,024 bytes. Operating systems often report sizes in binary units while drives are labelled in decimal ones.
Not always. Volume units like the pint and gallon differ between US and imperial systems. This tool uses US definitions for those cooking and liquid measures.
Yes — use the ⇅ button between the "From" and "To" selectors to reverse the conversion instantly.