Inches to Hectometers (in to hm)

1 inch equals 0.000254 hectometers exactly.

1 inch = 0.000254 hectometers

How to convert inches to hectometers

To convert inches to hectometers, multiply the number of inches by 0.000254. This factor is exact. To go the other way, multiply hectometers by 3,937.007874 (rounded).

hectometers = inches × 0.000254

Example: 10 inches = 0.00254 hectometers.

About these units

Inch (in)

US & ImperialCurrent unit

1/12 of a foot. Defined as exactly 25.4 millimeters since 1959, when the US and Commonwealth countries agreed a common international inch.

Latin uncia, meaning one-twelfth, is the root of both inch and ounce, and it passed into Old English as ynce. Roman measurers divided their foot into twelve unciae, and the English inch kept that twelfth. After 1066 an inch was reckoned as three barleycorns, and a 1324 statute attributed to Edward II spelled out the definition as three grains of barley, dry and round, placed end to end lengthwise. For centuries the inch was simply a twelfth of a foot, or a thirty-sixth of a yard, and the US and UK each kept their own copy of the standard yard.

Those copies differed slightly until the 1959 international agreement fixed the yard at exactly 0.9144 meter, which made the inch exactly 25.4 millimeters. The US adopted it in 1959 and the UK ratified it in 1963, effective 1964. Today the inch is still the customary unit in the United States and Canada, and the UK keeps it on road signs. Worldwide it also names display diagonals, wheel rims, tire codes and pipe sizes.

1 inch = 0.0254 meters (exactly).

Sources: Wikipedia: Inch; Wikipedia: Yard; NIST Guide to the SI, Appendix B.8: conversion factors

Hectometer (hm)

Metric (SI)Current unit

100 meters. An official SI unit, rarely used.

Hecto, the prefix for one hundred, dates to 1795 in Wikipedia's table of metric prefixes, which makes the hectometer (hm) a contemporary of the original French system. It equals 100 meters, one tenth of a kilometer, or about 328 feet. English speakers rarely use it, and the Wikipedia article flags even that claim as lacking a citation.

Its best-known appearance is hidden in another word. The hectare is a square hectometer, 10,000 square meters, so every land listing in hectares quietly rests on this length. A football pitch is about one hectometer long, and the Great Pyramid of Giza, at 137.7 m, stands about 1.377 hm high. Military writers have occasionally given target ranges in hectometers, with Wikipedia citing a 1927 Field Artillery Journal among its examples. The unit sits between the decameter at 10 m and the kilometer at 1,000 m.

1 hectometer = 100 meters (exactly).

Sources: Wikipedia: Hectometre; Wikipedia: Metric prefix; NIST: metric (SI) prefixes

Related conversions

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