Calculators & ProductivityRuns in your browserNew

Unit Converter

Convert twelve categories of measurement units.

Runs in your browserUpdated 2026-11-10 Report a problem

What this unit converter does

Unit Converter covers length, mass, temperature, area, volume, speed, time, data storage, data rate, pressure, energy and angle. Choose a category, enter a value and see the equivalent in every unit in that category, not just the one you selected.

Conversions use exact defined factors where they exist — an inch is exactly 25.4 millimetres, a pound is exactly 0.45359237 kilograms — and are displayed with significant-digit formatting so very small and very large results stay readable.

Why use it

Convert a recipe or a specification without looking up factors.
Compare imperial and metric values in one table.
Check a temperature or pressure reading in another unit.

How to use it

1Choose a category.
2Enter the value and pick the source unit.
3Read the target value or scan the full table of equivalents.

Worked examples

Distance

Input

1 mile

Output

1.609344 kilometres

Temperature

Input

100 °F

Output

37.7778 °C

Common mistakes

Using US and UK liquid measures interchangeably; a US gallon is smaller than an imperial gallon.
Mixing decimal data units with binary units; a GB and a GiB differ by about 7%.
Applying a temperature difference as if it were an absolute conversion.

Frequently asked questions

Are the conversion factors exact?

They are the defined values for each pair of units. Display rounds to eight significant digits, which is enough for practical use.

Why are there two gallon entries?

The US gallon and the UK gallon are different volumes. Both are labelled so you can pick the right one.

Can I convert between categories?

No. Length and mass measure different things. Some compound units, such as speed, have their own category.

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