// free-tool
Pick your from and to units and type a value — the result updates live as you type, with a swap button and a quick list of common conversions. It's pure math running locally, so it works instantly and even offline.
no signup · no watermark · unlimited use
Conversions use exact standard definitions (e.g. 1 inch = 25.4 mm) computed in double-precision floating point, and results are shown with sensible rounding you can copy at full precision.
Only to load the page the first time. The conversion itself is pure local math — no network requests are made.
Yes — completely free, with no account, no watermarks and no file limits beyond what your device's memory can handle.
Convert between mg, g, kg, tonnes, ounces, pounds and stone.
Convert between Celsius, Fahrenheit and Kelvin.
Convert between mm², cm², m², km², hectares, acres, ft² and in².
Convert between ml, liters, m³, teaspoons, cups, pints, quarts and gallons (US & UK).
Convert between m/s, km/h, mph, knots and ft/s.
Convert between milliseconds, seconds, minutes, hours, days, weeks, months and years.
I build fast, privacy-first web applications with Next.js — these converters run entirely in the browser, and yours can too.