Recipes, online shopping, travel and homework constantly mix metric and imperial units. Pick a category, enter a value and see the conversion instantly. The tool works offline, so it is handy on a plane or abroad without data.
How to use
- Choose a category such as Length or Temperature.
- Enter a value and pick the units to convert from and to.
- The result updates as you type; use โ to swap the units.
Why this tool is safe
This page loads no tracking scripts, and its security policy forbids it from sending data to other servers. The work happens in your browser's memory and is gone when you close the tab.
Frequently asked questions
How accurate are the conversions?
The tool uses the exact international definitions (for example 1 inch = 2.54 cm, 1 pound = 0.45359237 kg) and shows up to 10 significant digits.
Does it work offline?
Yes. Once the page has loaded (or the app is installed) it works with no connection.
Which gallon is used?
Both are available: the US gallon (3.785 L) and the UK imperial gallon (4.546 L).
How do I get a circle's radius from its circumference?
Choose the Circle category, enter the circumference and pick Radius as the target. The tool uses r = C รท 2ฯ, d = 2r and area = ฯrยฒ. The result is in the same unit you measured in (cm, m, inchesโฆ).