Convert Inches (in) to Millimeters (mm)

Enter a value below to convert Inches (in) to Millimeters (mm).

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Conversion:

1 Inches (in) = 25.4 Millimeters (mm)

How to Convert Inches (in) to Millimeters (mm)

1 in = 25.4 mm

1 mm = 0.03937007874 in

Example: convert 15 Inches (in) to Millimeters (mm):

25 in = 635 mm

Inches (in) to Millimeters (mm) Conversion Table

Inches (in)Millimeters (mm)
0.01 in0.254 mm
0.1 in2.54 mm
1 in25.4 mm
2 in50.8 mm
3 in76.2 mm
5 in127 mm
10 in254 mm
20 in508 mm
50 in1270 mm
100 in2540 mm
1000 in25400 mm

Inches (in)

Definition

An inch (in) is an imperial unit of length equal to 1/12 of a foot or exactly 25.4 millimeters.

History

The inch has ancient origins, historically defined as the width of a man's thumb. It was standardized internationally in 1959 to exactly 25.4 mm. The word 'inch' derives from the Latin 'uncia' meaning one-twelfth.

Current use

Inches are widely used in the United States, Canada, and the United Kingdom for everyday measurements: screen sizes, paper dimensions, height measurements, pipe diameters, and construction specifications.

Millimeters (mm)

Definition

A millimeter (mm) is a metric unit of length equal to one thousandth of a meter (0.001 m). There are 10 millimeters in a centimeter.

History

The millimeter derives from the metric system established in France in 1795. It became widely used in engineering and manufacturing as precision requirements increased during the Industrial Revolution.

Current use

Millimeters are standard in engineering drawings, precision machining, medical measurements (tumor sizes), rainfall measurement, and small-scale construction specifications worldwide.