Inch to Millimetre

Convert inches to millimetres. This calculator will convert inches, inches plus a fraction or a fraction of an inch to millimetres. Multiply the inch amount by 25.4 to get millimetres.

How do you convert an inch to a millimetre?

one inch (in) equals 25.4 millimetres (mm)
one millimetre (mm) equals 0.0393700787401575 inches (in)

Calculator

1. enter the inch amount
2. decimal precision, the number of digits after the decimal point

Result

1. inches converted to millimetres

Example Conversion:

convert 22 3/8 inches to millimetres

covert the fraction to a decimal by dividing the numerator by the denominator

3 ÷ 8 = 0.375

22 + 0.375 = 22.375

one inch = 25.4 millimetres

22.375  * 2.54 =  568.325

22 3/8" = 568.325 mm

convert 12/14 inches to millimetres

convert 3/8 to a decimal format by dividing the numerator by the denominator

12 ÷ 14 =  0.857142857

one inch = 2.54 millimetres

0.857142857 * 2.54 = 21.77

12/14" = 21.77 mm