Millimetres to Inches
Convert millimetres to inches (mm to in). 1 mm = 0.0393700787402 in. Use the calculator, formula and conversion table.
How to convert millimetres to inches
Multiply the amount in millimetres by 0.0393700787402 to get inches. The displayed factor and results are rounded to 12 significant digits.
in = mm × 0.0393700787402Worked example
1 mm = 0.0393700787402 in. Change the amount in the calculator above to use your own value.
Units and assumptions
Uses international metric and imperial definitions. One inch is exactly 0.0254 metres; one foot is 12 inches. These are lengths, rather than areas or volumes.
Calculator results use floating-point arithmetic and are rounded for display. The reference table below uses up to 12 significant digits.
Millimetres to Inches table
| Millimetres (mm) | Inches (in) |
|---|---|
| 0 | 0 |
| 1 | 0.0393700787402 |
| 5 | 0.196850393701 |
| 10 | 0.393700787402 |
| 25 | 0.984251968504 |
| 100 | 3.93700787402 |
| 1,000 | 39.3700787402 |
About this conversion
What is the formula for millimetres to inches?
in = mm × 0.0393700787402. Multiply the amount in millimetres by 0.0393700787402 to get inches. The displayed factor and results are rounded to 12 significant digits.
How do I convert back to millimetres?
Use the inches to millimetres calculator to reverse this conversion. You can also use Swap units in the calculator above.
Can I use a different pair of units?
Choose another unit in the calculator, or open the length converter to browse all supported pairs.