Inches to Millimeters Converter

One inch equals exactly 25.4 millimeters. This precision conversion is widely used in engineering, machining, and carpentry.

Formula

mm = in × 25.4Convert Inches (in) to Millimeters (mm).
Example: 0.25 in = 6.35 mm

Common Values

InchMillimeter
0.25 in6.35 mm
0.5 in12.7 mm
1 in25.4 mm
1.5 in38.1 mm
2 in50.8 mm
3 in76.2 mm
4 in101.6 mm
5 in127 mm
6 in152.4 mm
8 in203.2 mm
10 in254 mm
12 in304.8 mm

Unit Definitions

Inch
Symbol: in

The Inch (in) is a unit of length.

Millimeter
Symbol: mm

The Millimeter (mm) is a unit of length.

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