Convert Millimeters to Inches
Millimeters (mm) to Inches (in) — the formula, a worked example and a live converter, all in your browser.
Millimeters to Inches formula
To convert a measurement, multiply it by the fixed factor below:
in = mm × 0.03937007874
Worked example
1 mm = 1 × 0.03937007874 = 0.03937007874 in.
Millimeters to Inches conversion table
| Millimeters (mm) | Inches (in) |
|---|---|
| 1 | 0.03937007874 |
| 5 | 0.1968503937 |
| 10 | 0.3937007874 |
| 25 | 0.9842519685 |
| 50 | 1.968503937 |
| 100 | 3.937007874 |
Common uses
Frequently needed in engineering, woodworking and 3D printing, where drawings mix millimetre dimensions with imperial hardware.
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Frequently asked questions
What is the formula to convert millimeters to inches?
Multiply the number of millimeters by 0.03937007874 to get inches (in = mm × 0.03937007874).
How many inches are in a millimeter?
One millimeter equals 0.03937007874 inches.
Is this converter accurate?
Yes. It uses the exact internationally-defined conversion factors and runs entirely in your browser, so results match standards tables and nothing you type is uploaded.