Inch To Millimeter Conversion Chart

Inch (in) Millimeter (mm)
0.01 in0.254 mm
0.1 in2.54 mm
1 in25.4 mm
2 in50.8 mm
5 in127 mm
10 in254 mm
20 in508 mm
50 in1270 mm
100 in2540 mm
500 in12700 mm
1000 in25400 mm

Convert from inch to millimeter formula

Total millimeter = Total inch x 25.4

For example, if you want to convert 50 Inch to Millimeter then,

50 in = 50 x 25.4 = 1270 mm

Convert from millimeter to inch formula

Total inch =
Total millimeter
1270 mm
= 50 in


The inch (symbol: in) is a unit of length in the (British) imperial and United States customary systems of measurement. Standards for the exact length of an inch have varied in the past, but since the adoption of the international yard during the 1950s and 1960s, it has been based on the metric system and defined as exactly 25.4 mm.


A millimeter is the smallest unit. There are 10 mm in one centimeter, if an object is smaller than one centimeter, you would use millimeters. A scientist measuring something under a magnifying glass might use millimeters to represent a tiny specimen.