How to convert millimeters to inches
Millimeters and Inches both measure length, so converting is a single multiplication. One mm equals 0.03937 in, so you multiply your millimeters value by 0.03937.
Formula: inches = millimeters × 0.03937. For example, 10 mm = 0.393701 in.
Millimeters to Inches conversion table
| Millimeters (mm) | Inches (in) |
|---|---|
| 1 | 0.03937 |
| 2 | 0.07874 |
| 5 | 0.19685 |
| 10 | 0.393701 |
| 25 | 0.984252 |
| 50 | 1.968504 |
| 100 | 3.937008 |
| 1,000 | 39.370079 |
Millimeters and Inches explained
Millimeters (mm): One-thousandth of a metre, used for small, precise measurements like rainfall or engineering tolerances.
Inches (in): An imperial unit equal to exactly 2.54 cm, used for screens, print and DIY.
When you'd convert millimeters to inches
You'll convert millimeters to inches whenever a measurement is given in one unit but you need it in the other — comparing millimeters and inches figures across regions, following a recipe or spec, or double-checking a number. Because 1 mm is exactly 0.03937 in, the result is precise every time.
Frequently asked questions
How many inches are in a millimeter?
One mm equals 0.03937 in. Multiply your millimeters figure by 0.03937 to get inches.
What is the formula to convert millimeters to inches?
inches = millimeters × 0.03937. The factor 0.03937 is exact.
What is 2 millimeters in inches?
2 mm = 0.07874 in. You can enter any value in the converter above to get an instant result.
Is this Millimeters to Inches converter accurate?
Yes. It uses the standard conversion factor (1 mm = 0.03937 in) defined by BIPM — SI Brochure (definition of the metre), so results are exact to several decimal places.