Universal Unit Converter

All-in-one unit converter for length, weight, temperature, volume, area, speed, energy, and pressure. Convert between imperial and metric units instantly.

Eight measurement families share one page, and each keeps its own pivot quantity: metres for length, kilograms for weight, litres for volume, square metres for area, metres per second for speed, joules for energy and pascals for pressure. Temperature is handled apart from all of them, because a scale with an offset zero cannot be expressed as a single factor, so that category runs the Celsius, Fahrenheit and Kelvin formulas directly. Only three figures are shown at the top — a Primary Conversion, the formula sentence behind it, and your value restated in the family's pivot unit — with the full unit-by-unit breakdown in the table below. The Primary Conversion target is picked for you rather than chosen: it is the first unit of the selected family, or the second if you entered the first. That is why the default of 1 inch reports 0.083333 feet with a base value of 0.0254 metres, and why weight answers arrive in grams and pressure answers in pascals. Two behaviours differ from the single-purpose converters on this site. The value field accepts negatives all the way to -999,999,999, which temperature needs and which the linear families will not stop you using. And results are rounded to six decimals, switching to six significant figures once a number falls below a millionth or climbs past a trillion. Nothing crosses between families: there is no density to turn a volume into a mass, no compound units such as fuel economy or flow rate, and no time.