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1 in = 25.4 millimeters
1 inches = 25.4 millimeters
Free, instant, and 100% private — every calculation runs in your browser. Nothing is uploaded.
1 inch equals 25.4 millimeters. To convert inches to millimeters, multiply the value by 25.4.
1 inch = 25.4 millimeters. Formula: value × 25.4
Example: 1 in → 25.4 mm. Type any value in the converter above to see it converted live.
| Inches (in) | Millimeters (mm) |
|---|---|
| 1 in | 25.4 mm |
| 2 in | 50.8 mm |
| 5 in | 127 mm |
| 10 in | 254 mm |
| 25 in | 635 mm |
| 50 in | 1,270 mm |
| 100 in | 2,540 mm |
| 250 in | 6,350 mm |
| 500 in | 12,700 mm |
| 1,000 in | 25,400 mm |
1 inch = 25.4 millimeters. Formula: value × 25.4. Enter the value above and the result appears instantly — the calculation runs entirely in your browser.
Exactly: 1 inch = 25.4 millimeters. The reverse factor is 1 millimeter = 0.03937007874015748 inches.
1 in = 25.4 mm; 10 in = 254 mm; 100 in = 2,540 mm. Use the full conversion table below for more reference values.
Yes. Since 1959 the inch has been defined internationally as exactly 2.54 centimeters, so conversions between inches, feet, yards, and miles and the metric units are exact, not approximations.