Inches to Ken (in to ken)

1 inch equals 0.01397 ken exactly.

1 inch = 0.01397 ken

How to convert inches to ken

To convert inches to ken, multiply the number of inches by 0.01397. This factor is exact. To go the other way, multiply ken by 71.58196135 (rounded).

ken = inches × 0.01397

Example: 10 inches = 0.1397 ken.

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

Ken (ken)

JapaneseTraditional unit (still used in some regions)

Six shaku, exactly 20/11 meter (about 1.818 m). The traditional spacing of pillars in Japanese buildings; a tatami mat is half a ken wide in the Nagoya size.

Ken is the Japanese reading of the Chinese character jian, which means room, gap or interval. The name fits its job: the distance between two pillars of a building became a unit of measure, and land surveyors then used it when assessing taxes.

Its size has not always been the same. Under Toyotomi Hideyoshi in the 16th century it was about 1.97 meters, but around 1650 the Tokugawa shogunate shortened it to 1.818 meters, which raised the tax take. Since 1891 it has been exactly six shaku, or 20/11 meter. The longer old measure lives on in the Kyoto room size called kyoma.

Floor plans still lean on the ken. A tatami mat measures one half ken by one ken in the common Nagoya size, and a square ken of floor is a tsubo, about 3.31 square meters. The ken also fixes the length of the bo staff in Japanese martial arts.

1 ken = 1.818181818 meters (approximately).

Sources: Wikipedia: Ken (unit); Wikipedia: Tatami; Wikipedia: Japanese units of measurement

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