Convert Inches to Millimeters
Convert inches to millimeters instantly. Free, accurate, with a reference table for common values (1 in = 25.4 mm exactly).
1 in = 25.4 mm
Common length conversions
- 1 m = 3.280839895 ft
- 1 km = 0.6213711922 mi
- 1 cm = 0.3937007874 in
- 1 in = 2.54 cm
- 1 mi = 1.609344 km
- 1 ft = 0.3048 m
Formula
mm = inches × 25.4
Built-in to the calculator above — no need to do the math by hand.
Inches to Millimeters table
| in | mm |
|---|---|
| 1 in | 25.4 mm |
| 2 in | 50.8 mm |
| 3 in | 76.2 mm |
| 5 in | 127 mm |
| 10 in | 254 mm |
| 25 in | 635 mm |
| 50 in | 1270 mm |
| 100 in | 2540 mm |
| 250 in | 6350 mm |
| 500 in | 12700 mm |
| 1000 in | 25400 mm |
About Inches to Millimeters
Converting inches to millimeters is one of the most common length conversions people search for — used in trade, engineering, cooking, travel, and everyday problem-solving. The math itself is a fixed conversion factor (mm = inches × 25.4), but doing it by hand every time is slow and error-prone. This page gives you an instant live converter, a reference table for common values, and the formula broken out so you can trust the result. Everything runs in your browser, and the conversion happens the moment you type — no button to press, no reload, no upload.
How to convert in to mm
- 1Type your value in the Inches input above.
- 2The Millimeters result updates instantly to the right precision.
- 3Compare against the reference table below for common values.
- 4Copy the answer or bookmark the page for next time.