Convert Inch to Millimetre
Instant length conversion, with the formula and a full reference table.
1 in
25.4 mm
1 mm = 0.03937008 in
How to convert Inch to Millimetre
Multiply the number of inch by 25.4.
mm = in × 25.4
To go the other way, divide instead — or multiply by 0.03937008.
Worked example
To convert 25 in: 25 × 25.4 = 635 mm.
Inch to Millimetre conversion table
| Inch (in) | Millimetre (mm) |
|---|---|
| 1 | 25.4 |
| 2 | 50.8 |
| 3 | 76.2 |
| 5 | 127 |
| 10 | 254 |
| 20 | 508 |
| 25 | 635 |
| 50 | 1,270 |
| 100 | 2,540 |
| 250 | 6,350 |
| 500 | 12,700 |
| 1,000 | 25,400 |