Unit Converter

Unit Converter is a free math & calculators tool that runs entirely in your browser — length, mass, data, temperature. No upload, no account, no limits.

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How to use Unit Converter

Open the Unit Converter tool.
Paste or type your number into the input field.
The output updates as you type — adjust the options if you need a different format.
Copy the result, or share the URL to hand the exact input to someone else.

About Unit Converter

Convert between units across six families: length, mass, data, speed, time and temperature. Pick a category, choose the from and to units, and the converted value updates live with a copy-ready summary.

Covers everyday units like km, miles, kg, pounds, MB, GB, km/h, mph, hours, seconds and °C/°F/K.

What people use it for

Convert kilometres to miles or metres to feet.
Convert kilograms to pounds, or megabytes to gibibytes.
Convert °C to °F, or km/h to mph.

Frequently asked questions

Which unit categories are included?

Length, mass, data size, speed, time and temperature, each with the common units.

Does it handle temperature properly?

Yes — Celsius, Fahrenheit and Kelvin use the correct offset conversions, not simple ratios.

Is it private?

Every calculation happens on this page, in your own browser. Your input is never sent to a server, never logged and never used for training — which also means the tool keeps working when you are offline.