Inches to Millimeters
1 inch is 25.4 millimeters.
- To convert inches to millimeters, multiply the number of inches by 25.4.
- Going the other way, 1 millimeter is 0.0393701 inches.
- For example, 1.5 inches is 38.1 millimeters.
Conversion
Inches → Millimeters
38.1
1.5 inches equals this many millimeters
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| Inches (in) | Millimeters (mm) |
|---|---|
| 0.0625 | 1.59 |
| 0.125 | 3.18 |
| 0.25 | 6.35 |
| 0.375 | 9.52 |
| 0.5 | 12.7 |
| 0.625 | 15.88 |
| 0.75 | 19.05 |
| 1 | 25.4 |
| 1.5 | 38.1 |
| 2 | 50.8 |
| 3 | 76.2 |
| 4 | 101.6 |
| 6 | 152.4 |
| 8 | 203.2 |
| 10 | 254 |
| 12 | 304.8 |
About inches and millimeters
Fractional inches are common on U.S. tape measures and wrench sets; converting to millimeters is exact because one inch is defined as 25.4 mm. 1/16 inch is 1.5875 mm, the smallest mark on most tape measures.
Frequently asked questions
- How many millimeters are in a inch?
- There are 25.4 millimeters in one inch. To convert inches to millimeters, multiply the number of inches by 25.4.
- How do I convert 1.5 inches to millimeters?
- Multiply 1.5 by 25.4: 1.5 inches is 38.1 millimeters.
- What is 1/8 inch in millimeters?
- 1/8 inch is 0.125 in, which is exactly 3.175 mm.