Convert mm to in
A practical reference for converting millimeters (mm) to inches (in), a length unit. Type any value for an instant result, or use the reference table below.
1 mm = 0.03937 in
in = mm × 0.03937007874
Conversion formula
in = mm × 0.03937007874Divide millimeters by 25.4. Common in bolt and screw specifications.
Quick reference table
| millimeters | inches |
|---|---|
| 1 mm | 0.0394 in |
| 5 mm | 0.1969 in |
| 10 mm | 0.3937 in |
| 20 mm | 0.7874 in |
| 25 mm | 0.9843 in |
| 50 mm | 1.9685 in |
| 100 mm | 3.937 in |
| 200 mm | 7.874 in |
| 500 mm | 19.685 in |
| 1,000 mm | 39.3701 in |
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Open Unit ConverterFrequently asked questions
How many in is 1 mm?
1 mm equals 0.03937 in.
Why does my result differ slightly from other sites?
Rounding. This page displays four decimal places while the underlying calculation keeps full precision.
Is my input sent to a server?
No. Every calculation runs locally in your browser and nothing is transmitted.
All calculations on this page run in your browser. Your input is never sent to a server.