Conversion Calculators

Most conversions are one multiplication — the hard part is trusting the factor. Every converter here uses the internationally defined value (1 inch is exactly 25.4 mm, 1 pound is exactly 0.45359237 kg) rather than a rounded approximation, and shows the factor it used so you can check the arithmetic yourself.

Currency is the exception: rates move, so that tool fetches a live mid-market rate and stamps it with the time it was pulled. Everything else is pure math running on your device — type a number and the answer is there before you finish, with no round-trip to a server and nothing stored.