About UnitSwapper
A unit converter that shows its work: every result comes with the factor or formula that produced it, a reference table, and a page explaining where the factor comes from.
Who makes it
UnitSwapper is built and maintained by Dizzus GmbH, a small Swiss IT company based in Zug. There is no editorial team behind it and no sponsored content: the factors, formulas and explanations are written by the publisher and checked against the international definitions listed on the methodology page.
What it covers
107 units in 12 categories (length, weight, temperature, area, volume, speed, data, time, pressure, energy, power and fuel economy), plus currency conversion with European Central Bank reference rates and history back to 1999. Conversions run in your browser; nothing you type is sent anywhere.
How results are computed
Each unit is defined by its exact factor to the SI base unit of its category (metre, kilogram, second, square metre, cubic metre, metre per second, byte, pascal, joule, watt). A conversion multiplies by the source factor and divides by the target factor, so a chain such as inch → centimetre → inch returns exactly the starting value. Temperature and fuel economy use their own formulas because they are not proportional. Displayed values are rounded to six significant digits; the API returns full precision.
Found a mistake?
Write to [email protected] with the page URL and the source you are comparing against. Corrections are applied within days and noted on the methodology page.