Common Converters

Convert Inches to Millimeters

Use our accurate converter to change inches into millimeters. This tool is simple to use and works instantly.

How to Calculate

To change inches to millimeters, you just need to know the conversion factor.

Rule: 1 Inches = 25.4 Millimeters

Inches to Millimeters
Pre-defined calculator for direct inches to millimeters conversion.
Inches (in)
0
Millimeters (mm)
Formula: 1 Inches = 25.4 Millimeters

Unit Information

About Inches

Definition: An inch is a small unit of length used mostly in the USA.

History: The word comes from a Latin word meaning 'one-twelfth' of a foot.

Where it is used: Used for screen sizes, tools, and daily measurements in the USA and Canada.

Inches to Millimeters Conversion Table

Inches [in]Millimeters [mm]
0.01 in0.254 mm
0.1 in2.54 mm
1 in25.4 mm
2 in50.8 mm
3 in76.2 mm
5 in127 mm
10 in254 mm
20 in508 mm
50 in1,270 mm
100 in2,540 mm
1000 in25,400 mm

How to Convert Inches to Millimeters

Calculation: To convert inches to millimeters, multiply the value by the conversion factor (25.4).

Example: convert 15 in to mm:
15 in = 15 × 25.4 mm = 381 mm

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