Millimeters to Inches Converter
Use this free millimeters to inches converter to get an exact answer as you type. 1 millimeter equals 0.03937008 inches, so the conversion is simple – the calculator also accepts fractions such as 5 3/8 and shows the result as a fraction of an inch when it helps.
How to convert millimeters to inches
- Type the length in millimeters into the Value box. Fractions like 3/8 and mixed numbers like 5 3/8 are accepted.
- Check that “From” shows millimeters and “To” shows inches. Use the swap button to reverse the direction.
- Read the exact answer instantly. Choose how many decimals you need, and copy the result with one tap.
The millimeters to inches formula
To convert millimeters to inches, divide the number of mm by 25.4. In short: in = mm ÷ 25.4. Example: 50 mm = 1.9685 in.
Millimeters to inches conversion table
Look up the most common values below. For any other number, use the calculator above.
| Millimeters (mm) | Inches (in) |
|---|---|
| 1 | 0.0394 |
| 2 | 0.0787 |
| 3 | 0.1181 |
| 4 | 0.1575 |
| 5 | 0.1969 |
| 6 | 0.2362 |
| 7 | 0.2756 |
| 8 | 0.315 |
| 9 | 0.3543 |
| 10 | 0.3937 |
| 12 | 0.4724 |
| 14 | 0.5512 |
| 15 | 0.5906 |
| 16 | 0.6299 |
| 18 | 0.7087 |
| 20 | 0.7874 |
| 22 | 0.8661 |
| 24 | 0.9449 |
| 25 | 0.9843 |
| 28 | 1.1024 |
| 30 | 1.1811 |
| 32 | 1.2598 |
| 35 | 1.378 |
| 40 | 1.5748 |
| 45 | 1.7717 |
| 50 | 1.9685 |
| 60 | 2.3622 |
| 70 | 2.7559 |
| 75 | 2.9528 |
| 80 | 3.1496 |
| 90 | 3.5433 |
| 100 | 3.937 |
| 125 | 4.9213 |
| 150 | 5.9055 |
| 175 | 6.8898 |
| 200 | 7.874 |
| 250 | 9.8425 |
| 300 | 11.811 |
| 400 | 15.748 |
| 500 | 19.685 |
| 750 | 29.5276 |
| 1,000 | 39.3701 |
About these units
The millimeter (mm) is one thousandth of a meter. It is the standard unit for precise measurements in engineering, woodworking, 3D printing and hardware.
The inch (in or ″) is defined as exactly 2.54 centimeters. It is used in the United States, the United Kingdom and Canada, and for screen sizes, tires and pipes worldwide.
Frequently asked questions
How many inches are in 1 mm?
1 mm = 0.03937008 in. This factor is rounded to 7 significant digits; the calculator uses the exact ratio.
How do I convert millimeters to inches?
Divide the value in mm by 25.4. For example, 50 mm = 1.9685 in.
How many inches is 100 mm?
100 mm = 3.937 in.
Is this millimeters to inches converter accurate?
Yes. It uses the exact international definitions (1 inch = 2.54 cm, 1 foot = 30.48 cm). Numbers are rounded only for display, and you can show up to 8 decimals.