Millimeters To Inches Calculator

Millimeters To Inches - Calculate construction and material requirements accurately.

Millimeters To Inches Calculator

Millimeters & Inches Converter

Real-time two-way conversion

Enter a value in either field:

mm
in

Conversion Formula

This converter uses the exact international definition:

1 inch = 25.4 millimeters

1 millimeter = 1 / 25.4 inches

Millimeters To Inches Calculator Guide

The Metric Divide

The world uses Metric (mm), but the US construction industry uses Imperial (Inches). Translating between them is a daily task for engineers and builders working with imported materials.

The Magic Number

1 Inch = 25.4 Millimeters
To go from mm to inches: Divide by 25.4
To go from inches to mm: Multiply by 25.4

Cheat Sheet

Small Scale

  • 1/8 inch: ~3 mm
  • 1/4 inch: ~6 mm
  • 1/2 inch: ~13 mm
  • 3/4 inch: ~19 mm

Large Scale

  • 1 inch: 25.4 mm
  • 4 inches: ~100 mm
  • 12 inches (1 foot): 304.8 mm
  • 1 meter: 39.37 inches

Frequently Asked Questions

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