Millimeters to Inches conversion

Enter millimeters:		mm
	Convert Reset Swap
Inches decimal result:		″
Inches fraction result(*):		″
Feet+inches result:		″
Calculation:

* The fraction result is calculated by rounding the decimal inches to the closest 1/64 fraction.

Inches to mm ►

Millimeters to Inches

A millimeter (symbol: mm) is a unit of length in the International System of Units (SI). One millimeter is equal to one-thousandth (1/1,000) of a meter, which is defined as the distance light travels in a vacuum in a 1/299,792,458 second time interval.

The millimeter, or millimetre, is a multiple of the meter, which is the SI base unit for length. In the metric system, "milli" is the prefix for 10^-3. Millimeters can be abbreviated as mm; for example, 1 millimeter can be written as 1 mm.

An inch (symbol: in) is a unit of length in the imperial and US customary systems of measurement. An inch was defined to be equivalent to exactly 25.4 millimeters in 1959. There are 12 inches in a foot and 36 inches in a yard.

The inch is mostly used in the United States, Canada, and the United Kingdom. It is also sometimes used in Japan (as well as other countries) in relation to electronic parts, like the size of display screens.

How to convert millimeters to inches

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

Example

Convert 20 mm to inches:

d(″) = 20mm / 25.4 = 0.7874″

Millimeters to inches conversion table

The fraction inches are rounded to 1/64 resolution.

Inches to mm ►