inch to millimeter (in → mm)

Unit Converter

Converting inch (in) to millimeter (mm), 1in is about 25.4mm.

What is it

inch is a length unit, as is millimeter. Their relation is fixed: 1in = 25.4mm.

mm = in × 25.4

How to use

  1. 1Enter the inch (in) value.
  2. 2See the millimeter (mm) result instantly.
  3. 3Switch units to convert again if needed.

Reference

inch to millimeter (in → mm) Reference
inmm
125.4
5127
10254
501,270
1002,540
100025,400

Sources & standards

FAQ

How many mm is 1in?

1in is about 25.4mm.

How do I convert mm back to in?

Compute in = mm ÷ 25.4.

How many mm is 10in?

10in is about 254mm.

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