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Convert inches to mm

Please provide values below to convert inch [in] to millimeter [mm], or vice versa.

From: inch
To: millimeter
     

Inch

Definition: 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.

History/origin: The term "inch" was derived from the Latin unit "uncia" which equated to "one-twelfth" of a Roman foot.

There have been a number of different standards for the inch in the past, with the current definition being based on the international yard. One of the earliest definitions of the inch was based on barleycorns, where an inch was equal to the length of three grains of dry, round barley placed end-to-end. Another version of the inch is also believed to have been derived from the width of a human thumb, where the length was obtained from averaging the width of three thumbs: a small, a medium, and a large one.

Current use: 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.

Millimeter

Definition: A millimeter (symbol: mm) is a unit of length in the International System of Units (SI). It is defined in terms of the meter, as 1/1000 of a meter, or the distance traveled by light in 1/299 792 458 000 of a second.

History/origin: The milli- prefix is one of many metric prefixes. It indicates one thousandth of the base unit, in this case the meter. The definition of the meter has changed over time, the current definition being based on the distance traveled by the speed of light in a given amount of time. The relationship between the meter and the millimeter is constant however. Prior to the current definition, the meter was based on the length of a prototype meter bar. As with all SI units, the definition of the meter is subject to change, and it is possible that a new definition of the meter will be in place in the future.



Inch to Millimeter Conversion Table

Inch [in]Millimeter [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


How to Convert Inch to Millimeter

1 in = 25.4 mm
1 mm = 0.0393700787 in

Example: convert 15 in to mm:
15 in = 15 × 25.4 mm = 381 mm



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Convert Inch to Other Length Units

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inches to cm
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inches to yards
inches to feet
Inch to Light Year
Inch to Break
Inch to Exameter
Inch to Petameter
Inch to Terameter
Inch to Gigameter
Inch to Megameter
Inch to Hectometer
Inch to Dekameter
Inch to Micron
Inch to Picometer
Inch to Femtometer
Inch to Attometer
Inch to Megaparsec
Inch to Kiloparsec
Inch to Parsec
Inch to Astronomical Unit
Inch to League
Inch to Nautical League (UK)
Inch to Nautical League (int.)
Inch to League (statute)
Inch to Nautical Mile (UK)
Inch to Nautical Mile (international)
Inch to Mile (statute)
Inch to Mile (US Survey)
Inch to Mile (Roman)
Inch to Kiloyard
Inch to Furlong
Inch to Furlong (US Survey)
Inch to Chain
Inch to Chain (US Survey)
Inch to Rope
Inch to Rod
Inch to Rod (US Survey)
Inch to Perch
Inch to Pole
Inch to Fathom
Inch to Fathom (US Survey)
Inch to Ell
Inch to Foot (US Survey)
Inch to Link
Inch to Link (US Survey)
Inch to Cubit (UK)
Inch to Hand
Inch to Span (cloth)
Inch to Finger (cloth)
Inch to Nail (cloth)
Inch to Inch (US Survey)
Inch to Barleycorn
Inch to Mil
Inch to Microinch
Inch to Angstrom
Inch to A.u. Of Length
Inch to X-unit
Inch to Fermi
Inch to Arpent
Inch to Pica
Inch to Point
Inch to Twip
Inch to Aln
Inch to Famn
Inch to Caliber
Inch to Centiinch
Inch to Ken
Inch to Russian Archin
Inch to Roman Actus
Inch to Vara De Tarea
Inch to Vara Conuquera
Inch to Vara Castellana
Inch to Cubit (Greek)
Inch to Long Reed
Inch to Reed
Inch to Long Cubit
Inch to Handbreadth
Inch to Fingerbreadth
Inch to Planck Length
Inch to Electron Radius (classical)
Inch to Bohr Radius
Inch to Earth's Equatorial Radius
Inch to Earth's Polar Radius
Inch to Earth's Distance From Sun
Inch to Sun's Radius