Convert Millimeters to Inches
mm to in · length conversion
What are millimeters and inches?
A millimeter is one-thousandth of a meter, about the thickness of a credit card. An inch is an imperial unit equal to exactly 2.54 cm, widely used in the US and UK. For scale: a doorway is about 2 m (6.6 ft) tall, and a marathon is 42.2 km (26.2 mi).
How to convert millimeters to inches
1 mm = 0.0393701 in. To convert, multiply the number of millimeters by 0.0393701. For example, 5 mm = 0.19685 in, and 20 mm = 0.787402 in. To go the other way, multiply inches by 25.4 (since 1 in = 25.4 mm).
Millimeters to Inches conversion table
| Millimeters (mm) | Inches (in) |
|---|---|
| 1 | 0.0393701 |
| 2 | 0.0787402 |
| 5 | 0.19685 |
| 10 | 0.393701 |
| 20 | 0.787402 |
| 50 | 1.9685 |
| 100 | 3.93701 |
FAQ
What is 1 mm in in?
1 mm = 0.0393701 in. To convert any amount, multiply the number of millimeters by 0.0393701.
How do I convert inches back to millimeters?
Go the other way: 1 in = 25.4 mm, so multiply inches by 25.4 to get millimeters.
Is a millimeter bigger than a inche?
No — 1 mm is the smaller unit, equal to 0.0393701 in (it takes 25.4 mm to make one in).
Are these length conversions exact?
They use the standard internationally-defined conversion factors. Results are rounded to six significant figures for readability, which is accurate enough for everyday and most technical use.