Convert between every common unit of length and distance — from millimetres to nautical miles — with exact conversion factors and full precision.
Getting started
Enter a value and choose the unit you are converting from.
Select the unit you want to convert to — the result appears immediately.
Use the swap control to reverse the direction without retyping.
Why it helps
Uses exact internationally defined factors rather than rounded approximations.
Covers specialist units such as nautical miles alongside everyday ones.
Converts bidirectionally, so you can work in whichever direction fits the problem.
In practice
Converting a height or room measurement between metric and imperial.
Reading a distance given in miles when you think in kilometres.
Checking material dimensions given in a different unit system to your supplier's.
Everything people ask most about the length converter, answered plainly.
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