Convert Inch to Kilometer

Please provide values below to convert inch [in] to kilometer [km], or vice versa.

From:		inch
To:		kilometer

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.

Kilometer

Definition: A kilometer (symbol: km) is a unit of length in the International System of Units (SI). One kilometer is equivalent to 0.6214 miles.

History/origin: The prefix kilo- is a metric prefix indicating one thousand. One kilometer is therefore one thousand meters. The origin of the kilometer is linked to that of the meter, and its current definition as the distance traveled by light in 1/299 792 458 second. This definition is subject to change, but the relationship between the meter and the kilometer will remain constant.

Current use: It is currently the official unit of measurement for expressing distances between geographical places on land in most of the world. However, there still remain a number of countries that primarily use the mile instead of the kilometer including the United States and the United Kingdom (UK). Unlike the United States, the UK has adopted the metric system; while the metric system is widely used in government, commerce, and industry, remnants of the imperial system can still be seen in the UK's use of miles in its road systems.

Inch to Kilometer Conversion Table

How to Convert Inch to Kilometer

1 in = 2.54E-5 km
1 km = 39370.078740157 in

Example: convert 15 in to km:
15 in = 15 × 2.54E-5 km = 0.000381 km

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