UnitConConvert Inches to Millimeters
Convert inches to millimeters for machining, hardware, product design, and precise measurement. This page is useful where fractional inch references need metric equivalents.
Formula
Multiply inches by 25.4 to get millimeters. To reverse, divide millimeters by 25.4 to get inches.
Quick reference
| Inch (in) | Millimeter (mm) |
|---|---|
| 0.25 | 6.35 |
| 0.5 | 12.7 |
| 0.75 | 19.05 |
| 1 | 25.4 |
| 1.5 | 38.1 |
| 2 | 50.8 |
| 3 | 76.2 |
| 4 | 101.6 |
| 6 | 152.4 |
| 12 | 304.8 |