Inches to Millimeters Converter
Convert inches (in) to millimeters (mm). Type a number in either box and the result appears as you type.
Enter a number, for example 12.5
1 inch = 25.4 millimeters
Formula: mm = in × 25.4
How to convert inches to millimeters
1 inch = 25.4 millimeters
To convert inches to millimeters, multiply the value by 25.4.
Example: 5 in × 25.4 = 127 mm
Inches to Millimeters conversion table
| Inch (in) | Millimeter (mm) |
|---|---|
| 1 | 25.4 |
| 2 | 50.8 |
| 3 | 76.2 |
| 4 | 101.6 |
| 5 | 127 |
| 10 | 254 |
| 15 | 381 |
| 20 | 508 |
| 25 | 635 |
| 50 | 1,270 |
| 75 | 1,905 |
| 100 | 2,540 |
| 250 | 6,350 |
| 500 | 12,700 |
| 1,000 | 25,400 |
About inches and millimeters
Inch (in)
Exactly 2.54 centimeters. Used in the United States, and worldwide for screen and wheel sizes.
Millimeter (mm)
One thousandth of a meter. Used for small, precise measurements, such as parts, jewelry and rainfall.
Frequently asked questions
What is 1 in in millimeters?
1 in = 25.4 mm.
What is 1 mm in inches?
1 mm = 0.03937007874 in.
How do I convert inches to millimeters?
To convert inches to millimeters, multiply the value by 25.4. 1 inch = 25.4 millimeters.