Inches to Millimeters

From
To
Formula
mm = in × 25.4
Solution
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Answer
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Reverse conversion from Millimeters to Inches is available.

Common Cases

Facts

  • The inch was originally defined as the width of a man's thumb.
  • Screen sizes (phones, TVs, monitors) are measured in inches diagonally.
  • Pipe sizes and bolt sizes in the US are measured in inches.
  • One inch = 25.4 mm exactly, by international agreement.
Last Updated 2026-02-24 04:00:00 UTC