MM to Inches

The following is the mathematical connection between mm to inches: 0.0393701 inch = 1 millimetre 25.4 millimetres = 1 inch. Unit conversion is one of those tasks that we perform in our day to day life. In many situations, you may need to convert millimeters (mm) to inches (in). 

A millimeter is a small unit of displacement (length/distance) in the metric system. A millimeter is one thousandth of a meter. There are 25 millimeters in an inch. One millimetre is equal to 1000 micrometres or 1000000 nanometres. 

An inch can be defined as a unit of length in the customary system of measurement. The symbol for inches is the double prime (″), not double quotation marks (”) or straight quotation marks (") or (gasp!) two single quotation marks in a row ('').

To convert mm to inches, you must multiply the unit by 0.039.

Inches = MM X 0.0393701

For example, here's how to convert 5 mm to inches using the formula above.

5 mm = (5 ÷ 25.4) = 0.1968504"

a) 1 millimeter is equal to 0.03937007874 inches:

1mm = (1/25.4)″ = 0.03937007874″

The distance d in inches (″) is equal to the distance d in millimeters (mm) divided by 25.4:

d(″) = d(mm) / 25.4

b) Convert 20 mm to inches:

d(″) = 20mm / 25.4 = 0.7874″