Inches to Millimeters
1 in = 25.4 mm. Edit either value to convert instantly.
Conversion formula
mm = in × (0.0254) × (1,000)1 in = 25.4 mm
inch (in)
An inch is exactly 0.0254 m, or 2.54 cm; 12 inches make one foot.
millimeter (mm)
One millimeter equals exactly 0.001 m.
Source: BIPM SI Brochure, 9th edition — SI prefixes and accepted non-SI units
Conversion table
| in | mm |
|---|---|
| 1 | = 25.4 |
| = 50.8 | |
| = 127 | |
| = 254 | |
| = 381 | |
| = 508 | |
| = 635 | |
| = 762 | |
| = 1,016 | |
| = 1,143 |
| in | mm |
|---|---|
| = 1,270 | |
| = 1,524 | |
| = 1,778 | |
| = 2,032 | |
| = 2,286 | |
| = 2,540 | |
| = 3,810 | |
| = 4,064 | |
| = 4,318 | |
| = 4,572 |
Frequently asked questions
How many millimeters are in 1 inch?
1 in = 25.4 mm. mm = in × (0.0254) × (1,000)
How do I convert in to mm?
mm = in × (0.0254) × (1,000)
Is 1 inch bigger than 1 millimeter?
1 in = 25.4 mm.
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