Inches to Millimeters

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in
mm
1 in = — mm

Quick reference

Inches (in)Millimeters (mm)

Formula

millimeters = inches × 25.4

Multiply the inches value by 25.4 to get millimeters. To reverse — divide millimeters by 25.4 to get inches.

About this conversion

The inch (in) is an imperial unit equal to exactly 25.4 millimeters. Learn more →

The millimeter (mm) is a metric unit equal to one thousandth of a meter. Learn more →

Source: NIST International Reference