Inch to millimeter conversion
Inches to MM Converter
Convert inches to millimeters for hardware, product dimensions, technical drawings, and small measurements.
in
mm
10 in = 254 mm
10 × 25.4 = 254
1 inch = 25.4 mm
inches × 25.4 = millimeters
Common examples
A half inch is 12.7 mm, 2 inches is 50.8 mm, and 10 inches is exactly 254 mm. Millimeters are useful where centimeter precision is not detailed enough.
Related conversions
Use the inches-to-centimeters converter, compare values in the inch-to-cm chart, or open 10 inches in centimeters.
Frequently asked questions
How many millimeters are in one inch?
One inch equals exactly 25.4 millimeters.
How do you convert inches to millimeters?
Multiply the inch measurement by 25.4.
Is 10 inches exactly 254 mm?
Yes. Ten multiplied by the exact factor 25.4 equals 254 millimeters.