Type a value in inches to convert it to millimeters instantly. One inch equals 25.4 millimeters.
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How to use the Inches to Millimeters Converter
- 1
Enter the value in inches.
- 2
Read the result in millimeters; it updates as you type.
- 3
Use the swap button to convert in the other direction.
How to convert inches to millimeters
mm = in × 25.4. For example, 10 in = 254 mm.
Frequently asked questions
How many millimeters are in a inch?
One inch is 25.4 millimeters.