How to use Inches to Millimeters
Type a value in inches and the millimeters figure appears straight away. The conversion table further down lists common values.
How it works
Calculated from the inputs shown in this tool.
Examples
- 1 inches to millimeters
25.4 mm
- 10 inches to millimeters
254 mm
- 250 inches to millimeters
6,350 mm
Inches to Millimeters conversion table
| Inches | Millimeters |
|---|---|
| 1 | 25.4 mm |
| 2 | 50.8 mm |
| 3 | 76.2 mm |
| 4 | 101.6 mm |
| 5 | 127 mm |
| 6 | 152.4 mm |
| 7 | 177.8 mm |
| 8 | 203.2 mm |
| 9 | 228.6 mm |
| 10 | 254 mm |
| 15 | 381 mm |
| 20 | 508 mm |
| 25 | 635 mm |
| 30 | 762 mm |
| 40 | 1,016 mm |
| 50 | 1,270 mm |
| 75 | 1,905 mm |
| 100 | 2,540 mm |
| 250 | 6,350 mm |
| 500 | 12,700 mm |
| 1,000 | 25,400 mm |
Limitations and assumptions
Confirm assumptions, units and applicable local rules before relying on results. Detailed content, accessibility and edge-case review remains ongoing.
Frequently asked questions
How many millimeters are in one inch?
One inch equals 25.4 mm. The formula is Calculated from the inputs shown in this tool..
How do I convert inches to millimeters?
Use Calculated from the inputs shown in this tool.. For example, 10 inches gives 254 mm. Enter your own value above and the converter does the arithmetic for you.
How do I convert millimeters back to inches?
Use the Millimeters to Inches converter, or invert the factor by dividing instead of multiplying.
Is this conversion exact?
Every length conversion here hangs on one exact definition, 1 inch = 2.54 cm, so results are exact apart from display rounding.