Millimeters to inches (mm to in)
There are exactly 25.4 millimeters in an inch, so divide by 25.4. Handy anchors: 10 mm is about 0.394 in, 12.7 mm is exactly half an inch, and 6 mm is very close to 1/4 inch - the reason metric and imperial socket sets almost line up.
mm to in conversion table
| Millimeters (mm) | Inches (in) |
|---|---|
| 1 | 0.039 |
| 5 | 0.197 |
| 10 | 0.394 |
| 12.7 | 0.5 |
| 20 | 0.787 |
| 25.4 | 1 |
| 50 | 1.969 |
| 100 | 3.937 |
| 300 | 11.811 |
How to convert millimeters to inches
The formula is inches = millimeters ÷ 25.4. Type any value into the converter above for
an exact result, or use the table for the most common conversions. For other units, the
full length converter handles every combination, and
the unit converter covers length, weight, temperature,
speed, area, volume and data in one place.
Frequently asked questions
How many inches are in 1 millimeter?
1 mm = 0.0393701 in. The formula is inches = millimeters ÷ 25.4; the converter applies it to whatever you type and rounds only for display.
What is 20 mm in in?
20 mm = 0.787 in, using inches = millimeters ÷ 25.4.
How do I convert inches back to millimeters?
Use millimeters = inches x 25.4. For example, 2 in = 50.8 mm. The in to mm converter does this for you.