in to mm
Convert Inch to Millimeter
Convert Inch to Millimeter instantly with the tool above. The conversion factor is 25.4, meaning 1 inch equals 25.4 millimeters. Type any value and the result updates immediately — no ads, no page reloads, no clutter.
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1 Inch = 25.4 millimeters
1 Millimeter = 0.03937008 inches
Quick reference
Common inches converted to millimeters at a glance.
| in | mm |
|---|---|
| 1 | 25.4 |
| 2 | 50.8 |
| 5 | 127 |
| 10 | 254 |
| 25 | 635 |
| 50 | 1,270 |
| 100 | 2,540 |
| 500 | 12,700 |
| 1,000 | 25,400 |
How to convert inches to millimeters
To convert a value from inches to millimeters, multiply the inch value by 25.4 millimeters. For example, 10 inches × that factor = 254 millimeters.
This inch to millimeter converter runs entirely in your browser, so results appear instantly with no page reload, no advertisements and no sign-up.
Frequently asked questions
How many millimeters are in 1 inch?+
1 inch is equal to 25.4 millimeters.
How do you convert inches to millimeters?+
To convert inches to millimeters, multiply the inch value by 25.4. For example, 10 inches × 25.4 = 254 millimeters.
What is the formula to convert inches to millimeters?+
Inch → Millimeter: value × 25.4. Equivalently, 1 inch = 25.4 millimeters.
Is this Inch to Millimeter converter free to use?+
Yes. This inch to millimeter converter is completely free, works instantly in your browser, and contains no advertisements, popups or sign-up.