MM to Inches Converter
Type in either box to convert millimeters to inches or inches to millimeters, with the nearest 1/16-inch fraction for tools and hardware.
The formula
An inch is exactly 25.4 millimeters. Divide millimeters by 25.4 to get inches, or multiply inches by 25.4 to get millimeters.
10 mm = 0.3937008 in
mm to inches conversion table
| Millimeters (mm) | Inches |
|---|---|
| 0.5 | 0.019685 |
| 1 | 0.03937 |
| 2 | 0.07874 |
| 3 | 0.11811 |
| 4 | 0.15748 |
| 5 | 0.19685 |
| 6 | 0.23622 |
| 8 | 0.314961 |
| 10 | 0.393701 |
| 12 | 0.472441 |
| 15 | 0.590551 |
| 16 | 0.629921 |
| 20 | 0.787402 |
| 25 | 0.984252 |
| 30 | 1.1811 |
| 35 | 1.378 |
| 40 | 1.5748 |
| 50 | 1.9685 |
| 75 | 2.9528 |
| 100 | 3.937 |
Inches to mm conversion table
| Inches | Millimeters (mm) |
|---|---|
| 1/32″ (0.03125) | 0.79375 |
| 1/16″ (0.0625) | 1.5875 |
| 1/8″ (0.125) | 3.175 |
| 3/16″ (0.1875) | 4.7625 |
| 1/4″ (0.25) | 6.35 |
| 5/16″ (0.3125) | 7.9375 |
| 3/8″ (0.375) | 9.525 |
| 7/16″ (0.4375) | 11.1125 |
| 1/2″ (0.5) | 12.7 |
| 9/16″ (0.5625) | 14.2875 |
| 5/8″ (0.625) | 15.875 |
| 11/16″ (0.6875) | 17.4625 |
| 3/4″ (0.75) | 19.05 |
| 13/16″ (0.8125) | 20.6375 |
| 7/8″ (0.875) | 22.225 |
| 15/16″ (0.9375) | 23.8125 |
| 1 | 25.4 |
| 1 1/4″ (1.25) | 31.75 |
| 1 1/2″ (1.5) | 38.1 |
| 2 | 50.8 |
Good to know
Wrench and socket sizes don't map one-to-one: 13 mm is close to 1/2 inch (12.7 mm) and 19 mm to 3/4 inch (19.05 mm).
Rainfall is reported in inches in the US and in millimeters elsewhere: 1 inch of rain is 25.4 mm.
Sources
Frequently asked questions
How many mm is an inch?
Exactly 25.4 mm. Half an inch is 12.7 mm and a quarter inch is 6.35 mm.
What is 10 mm in inches?
0.394 inches, a little more than 3/8 inch (9.525 mm). That's why a 10 mm wrench is close to, but not the same as, a 3/8-inch one.
What fraction of an inch is 5 mm?
About 0.197 inches, closest to 3/16 inch (4.76 mm).