How many inch are in one millimeter?
One millimeter is 0.03937 in.
Millimeter to Inch
Type a value to convert it from millimeter to inch. One mm equals 0.03937 in.
Result
Millimeter and Inch, side by side
One millimeter is 0.03937 in. In the other direction, one inch is 25.4 mm.
The factor is exact rather than rounded: the imperial units have been defined from the metric ones since 1959, so the conversion introduces no error of its own. What you see below is arithmetic, not an approximation.
| Millimeter | Inch |
|---|---|
| 1 | 0.0393701 |
| 5 | 0.19685 |
| 10 | 0.393701 |
| 20 | 0.787402 |
| 50 | 1.9685 |
| 100 | 3.93701 |
Frequently asked questions
How do I convert inch back to millimeter?
One inch is 25.4 mm. The tool above converts in both directions.
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