About ChangingUnits

What we do

ChangingUnits is a free online tool that converts between hundreds of units across length, weight, temperature, area, volume, currency, energy, and more. Every converter is instant — results update as you type, no button press needed.

We cover units that other converters miss: obscure scientific units, regional measurements, and even a few fun ones like smoots and donkeypower.

Why we built this

Most unit converter sites are cluttered, slow, and designed around desktop computers from 2008. We wanted something that felt modern, loaded fast on any device, and gave you the answer without getting in the way.

Every converter page is built to one standard: the tool is the first thing you see, it works immediately, and there's nothing between you and your answer.

Accuracy

All conversions use exact or internationally recognised values. Where definitions differ between systems (such as US versus Imperial measurements), we clearly label which standard we are using. If you spot an error, please let us know.

Who is behind ChangingUnits

ChangingUnits is an independent project. We are a small team passionate about building useful tools that are free and accessible to everyone, anywhere in the world.