mm to inches

mm to inches – Quickly convert millimeters to inches with our free calculator. Learn the formula, definition, and view the conversion chart.

Millimeters to Inches Converter
Please enter a valid number.
0 inches

About the Millimeters to Inches Conversion

Converting millimeters to inches is a frequent task in engineering, manufacturing, and DIY projects. While millimeters provide high precision in the metric system, inches are the standard in the Imperial system. Our calculator above simplifies this process. Below is the explanation of the math involved.

Definitions

What is a Millimeter (mm)?

A millimeter (symbol: mm) is a unit of length in the metric system, equal to one-thousandth of a meter (0.001 m). It is commonly used for small scale measurements where precision is required.

What is an Inch (in)?

An inch (symbol: in or ) is a unit of length in the British imperial and United States customary systems. It is defined internationally as exactly 25.4 millimeters.


How to Convert Millimeters to Inches

The relationship between the millimeter and the inch is defined by the international yard agreement of 1959.
1 Inch = 25.4 Millimeters.

To convert millimeters to inches, you divide the length value by 25.4.

Formula:
Inches = Millimeters ÷ 25.4

Example Calculation:

  • Let’s say you have a length of 500 mm.
  • Calculation: 500 ÷ 25.4 = 19.685
  • Result: 500 mm is approximately 19.685 inches.

Quick Conversion Table: MM to Inches

Use this table to quickly find equivalent values for common millimeter measurements.

Millimeters (mm)Inches (in)
1 mm0.0394 in
5 mm0.1969 in
10 mm (1 cm)0.3937 in
25.4 mm1.0000 in
50 mm1.9685 in
100 mm3.9370 in
1000 mm (1 meter)39.3701 in