Convert Millimeters to inches
1 millimeter = 0.03937 inches · in = mm ÷ 25.4
When you need this conversion
This conversion goes from millimeters, the metric unit used for hardware, engineering drawings, and anything needing sub-centimeter precision, to inches, the US customary unit for screens, hardware, and short measurements. Both measure the same physical quantity, so the conversion is exact — the difference is which unit your source, tool, or region happens to use.
Millimeters to inches conversion table
| Millimeters (mm) | Inches (in) |
|---|---|
| 1 mm | 0.03937 in |
| 2 mm | 0.07874 in |
| 3 mm | 0.11811 in |
| 5 mm | 0.19685 in |
| 10 mm | 0.393701 in |
| 15 mm | 0.590551 in |
| 20 mm | 0.787402 in |
| 25 mm | 0.984252 in |
| 50 mm | 1.9685 in |
| 75 mm | 2.9528 in |
| 100 mm | 3.937 in |
| 250 mm | 9.8425 in |
| 500 mm | 19.685 in |
| 1,000 mm | 39.3701 in |
The formula
in = mm ÷ 25.4Because both units measure length, the conversion is a single multiplication by a fixed factor. That factor never changes, so the result is exact.
Convert the other way
Inches to millimeters →Related length conversions
- Millimeters to micrometers
- Centimeters to inches
- Centimeters to feet
- Meters to kilometers
- Kilometers to meters
- Inches to centimeters
- Feet to centimeters
- Feet to yards
- Yards to feet
- Micrometers to millimeters
- Millimeters to centimeters
- Millimeters to meters
Frequently asked questions
- How many inches are in a millimeter?
- There are 0.03937 inches in 1 millimeter. The formula is in = mm ÷ 25.4.
- How do you convert millimeters to inches?
- Use the formula in = mm ÷ 25.4. For example, 10 millimeters equals 0.393701 inches.
- Is the millimeters to inches conversion exact?
- Yes. Millimeters and inches are both units of length, related by an exact defined factor. Displayed results are rounded for readability.
- What is mm short for?
- mm is the standard symbol for millimeter (also written as millimetres). in is the symbol for inch.