Inches to Millimeters – in to mm

Use this simple calculator to convert inches to millimeters. Place your inch value in the blank space, and the equivalent millimeters will show. You can also use our inches-to-millimeters formula to make the calculations yourself.

Convert Inches(in) to Millimeters(mm)

Type a value in the Inches(in) field to convert the value to Millimeters(mm):


There are 25.4 millimeters in one inch. To convert from inches to millimeters, multiply your value by 25.4.

Millimeters = inches x 25.4

in to mm converter

Reference the table below for common inches to millimeters conversions.

Inches(in)Milimeters(mm)
1 in25.4 mm
1.5 in38.09 mm
2 in50.8 mm
2.2 in55.88 mm
3 in76.199 mm
3.75 in95.25 mm
4 in101.6 mm
4.25 in107.94 mm
5 in127 mm
5.5 in139.7 mm
6 in152.39 mm
7.5 in190.5 mm
8 in203.2 mm
10 in254 mm
10.5 in266.7 mm
12 in50.8 mm
13 in76.19 mm
15 in381 mm
16 in406.4 mm
18 in2057.4 mm
20 in508 mm
25 in635 mm
27 in685.8 mm
30 in762 mm
35 in889 mm
40 in1016 mm
48 in1219.19 mm
50 in1270 mm
80 in2032 mm
100 in2540 mm
200 in5080 mm
300 in7620 mm

How to Convert Millimeters to Other Measurements

Use the formulas below to convert millimeters to other units.

A millimeter is equal to 1/10th of a centimeter. So, to go from millimeters to centimeters, divide your value by 10.

Centimeters = millimeters ÷ 10

A decimeter is 1/10 of a meter and the equivalent of 100 millimeters. To convert from millimeters to decimeters, divide by 100.

Decimeters = millimeters ÷ 100

There are 304.8 millimeters in one foot. To figure millimeters to feet, divide by 304.8.

Feet = millimeters ÷ 304.8

There are 1,000 millimeters in a meter. To convert from millimeters to meters, divide by 1,000.

Meters = millimeters ÷ 1,000

There are 914.4 millimeters in a yard. To figure millimeters to yards, divide by 914.4.

Yards = millimeters ÷ 914.4


What is a Millimeter?

A millimeter (symbol: mm) is a unit of length from the metric system or International System of Units (SI). A millimeter is the smallest measurement on metric rulers and tape measures. One millimeter is one-tenth of a centimeter and 1/1000th of a meter.

Examples of a millimeter include the thickness of ten pieces of copy paper stacked on top of each other, the sharp point of a pencil, or the thickness of a driver’s license.


Millimeter vs. Inch

An inch is an imperial unit used in the United States and the United Kingdom. An inch is 25.4 times larger than a millimeter. A millimeter is a standard unit of measurement for countries that use the metric system, which includes most of the world. Since the millimeter is so tiny, it allows for precise measurements.


Frequently Asked Questions (FAQ)FAQ

What’s the difference between a millimeter and a cubic millimeter?

A standard millimeter measures length, while a cubic millimeter measures volume (length x width x height.) A cubic millimeter is a cube in which all sides measure one millimeter.

What’s the difference between a millimeter and a square millimeter?

A square millimeter measures area (length x width), while a standard millimeter only measures length. A square millimeter has four equal sides of one millimeter.

How big is a micrometer compared to a millimeter?

One millimeter contains 1,000 micrometers. So, a micrometer is 1/1000th of a millimeter.

How big is a nanometer compared to a millimeter?

There are 1,000,000 nanometers in a millimeter.

When should you use millimeters to measure?

Use millimeters to measure very small objects less than one centimeter. Using millimeters allows for preciseness.