Millimeters to Inches (mm to in)
Divide millimeters by 25.4 to get inches — an inch is exactly 25.4 mm. One millimeter is about 0.0394 inches, a little over 1/32 inch.
Inches
0.03937
Formula
inches = millimeters ÷ 25.4
Example: 4 millimeters = 0.15748 inches.
Millimeters to Inches chart
| millimeters | inches |
|---|---|
| 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 |
| 13 | 0.511811 |
| 15 | 0.590551 |
| 16 | 0.629921 |
| 19 | 0.748031 |
| 20 | 0.787402 |
| 25 | 0.984252 |
| 30 | 1.1811 |
| 50 | 1.9685 |
| 100 | 3.93701 |
Good to know
Workshop sizes: 6 mm ≈ 0.236 in (just under 1/4 in, which is 6.35 mm), 10 mm = 0.394 in, 13 mm ≈ 0.512 in (close to 1/2 in, 12.7 mm). Metric and imperial sockets and drill bits are close but not interchangeable at larger sizes.
Rainfall and snowfall: 25 mm of rain is just under an inch.
Frequently asked questions
How many inches is 1 mm?
0.03937 inches.
How many inches is 10 mm?
10 mm is 0.3937 inches — about 25/64 in.
How many mm is 1/4 inch?
1/4 inch is 6.35 mm.