Millimeters to Inches Converter
1 millimeter (mm) = 0.0393701 inches. Since 1 inch = 25.4 mm exactly, divide mm by 25.4 to convert.
Inverse conversion
1 inch (in) = exactly 25.4 millimeters (mm). 6 inches = 152.4 mm. 12 inches (1 ft) = 304.8 mm.
Formula
Formula
in = mm ÷ 25.4
Worked example
To convert 50 mm to inches, divide 50 ÷ 25.4. Result: 1.9685 inches.
Quick reference table
| mm | in |
|---|---|
| 1 | 0.03937 |
| 5 | 0.19685 |
| 10 | 0.393701 |
| 25 | 0.984252 |
| 50 | 1.968504 |
| 100 | 3.937008 |
| 200 | 7.874016 |
| 300 | 11.811024 |
Unit definitions
Millimeter (mm)
The millimeter (mm) is 1/1,000 of a meter. Widely used in engineering, manufacturing, and precision measurement.
Inch (in)
The inch (in) is defined as exactly 25.4 mm. Used in the US, UK, and Canada for engineering, screen sizes, and hardware.
Common use cases
- Reading metric caliper measurements in imperial
- Screen and display sizes (diagonal in inches)
- Fastener and pipe sizing
- Woodworking and metalworking plans