Free online unit converters
Free online converters for the measurements you meet every day, from kilometres and miles to kilograms, pounds and degrees. Results update as you type.
All converters
Exact factors, not rounded ones
Many quick conversion charts round their numbers, which adds up to real errors on large values. Our converters use the exact international definitions, such as 1 inch = 2.54 cm and 1 pound = 453.59237 g, and show results to six decimal places.
Converted a height or weight? Use it straight away in the BMI calculator, or turn inch paper sizes into millimetres for the paper weight calculator.