MM to inches formula
Exact conversion factor
Inches = Millimeters ÷ 25.4 Example: 50 mm ÷ 25.4 = 1.968 in This is an exact figure, not an approximation — it comes directly from the 1959 international agreement that defined 1 inch as exactly 2.54 cm, which every other unit here (feet, mm, meters, yards) also derives from. Unlike some unit pairs, there's no US-vs-UK version to worry about here.
Common reference points
| Millimeters | Inches |
|---|---|
| 1 mm | 0.039 in |
| 5 mm | 0.197 in |
| 10 mm | 0.394 in |
| 25 mm | 0.984 in |
| 50 mm | 1.968 in |
| 100 mm | 3.937 in |
| 250 mm | 9.842 in |
| 500 mm | 19.685 in |
Frequently asked questions
How many inches is 50 mm?
50 mm is about 1.97 inches.
How many mm are in an inch?
Exactly 25.4 millimeters.
How do I convert mm to inches?
Divide the millimeter value by 25.4.