About VersatilBox

Why we built this

Unit conversion is a solved problem that the web still makes surprisingly annoying: calculator sites bury the answer under ads, show different digits on every page, and never tell you where the factor came from. VersatilBox is our answer — 298 converters across 12 categories, each on a page that shows the number instantly, the formula behind it, and the definition that makes it exact.

Our methodology

Every factor on this site comes from an international definition, not a shortcut: the inch is exactly 25.4 millimeters, the pound exactly 0.45359237 kilograms, the nautical mile exactly 1,852 meters — as agreed by international treaty and published by the BIPM (International Bureau of Weights and Measures) and NIST (US National Institute of Standards and Technology).

Temperature uses the exact scale formulas between Celsius, Fahrenheit and Kelvin. Calendar time is the one place where "exact" needs a convention: months range from 28 to 31 days, so we use the Gregorian averages (1 month = 30.436875 days, 1 year = 365.2425 days) — the same convention that keeps the calendar aligned over its 400-year cycle — and we say so on every affected page. Digital storage uses decimal SI prefixes (1 kilobyte = 1,000 bytes), the standard of storage manufacturers, with the binary alternative explained in context.

Editorial standards

Each conversion page is written individually for its direction — converting meters to feet is not the same page as feet to meters — with its own formula, worked example, reference table and FAQ. When something is an approximation or a convention, the page says so in plain language. Corrections are welcome via the contact page and are applied quickly.

How the site is funded

VersatilBox is free and supported by display advertising served through Google AdSense. Ads are kept clearly separated from content and never interfere with the converter. See our privacy policy for details on cookies and your choices.