Convert Inches to Millimeters
One inch equals 25.4 millimeters. Type any value to convert inches to millimeters instantly — with a full reference table below.
Convert Inches to Millimeters
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Conversion formula
To convert inches to millimeters, multiply by 25.4. One inch equals 25.4 mm, and one millimeter equals 0.03937 in.
Inches to Millimeters table
About converting Inches to Millimeters
Inches (in) and Millimeters (mm) are both units of length. The exact factor is 1 in = 25.4 mm, so multiply by 25.4 to go from inches to millimeters (or divide to go back).
The conversion is exact and runs entirely in your browser. Need the reverse? Use the Millimeters to Inches converter, or the full unit converter for every unit at once.
Frequently asked questions
How many millimeters are in one inch?
One inch equals 25.4 millimeters.
How do I convert inches to millimeters?
Multiply the number of inches by 25.4. For example, 10 inches = 254 millimeters.
What is 5 inches in millimeters?
5 inches is 127 millimeters.