Jō (tatami Mat) to Square Miles (jō to mi²)

1 jō (tatami mat) equals 6.38185386×10⁻⁷ square miles (rounded).

1 jō (tatami mat) = 6.38185386×10⁻⁷ square miles

How to convert jō (tatami mat) to square miles

To convert jō (tatami mat) to square miles, multiply the number of jō (tatami mat) by 6.38185386×10⁻⁷. The factor is rounded to 10 significant digits. To go the other way, multiply square miles by 1,566,942.807 (rounded).

square miles = jō (tatami mat) × 6.38185386×10⁻⁷

Example: 10 jō (tatami mat) = 0.00000638185386 square miles.

Approximate value. Standards for the jō (tatami mat) varied by place and period, so this converter uses the most commonly cited value. Treat results as estimates, not exact figures.

About these units

Jō (tatami Mat) (jō)

JapaneseTraditional unit (still used in some regions)Approximate value

Half a tsubo, about 1.653 m², the area of one tatami mat. Mats vary by region from about 1.44 to 1.82 m², and Japanese real-estate rules set a minimum of 1.62 m² per jō in advertisements.

Jō is the counter for tatami, the woven rush floor mats of Japanese rooms, and the word tatami comes from a verb meaning to fold or pile, since early mats were thin enough to be stacked away. Tatami began as seating for the aristocracy in the Heian period and covered whole rooms in samurai and temple houses by the Muromachi era. They reached ordinary homes only in the late 17th century.

Because a mat was a standard building module, rooms are still described as six jō or eight jō. A mat is about twice as long as it is wide, and size varies by region. Kyoto mats measure about 191 by 95.5 cm, around 1.82 m2, Nagoya mats about 1.65 m2 and Tokyo mats about 1.55 m2. Apartment-block mats can be smaller, near 1.44 m2.

Wikipedia takes the Nagoya mat as the reference, which makes one jō half a tsubo, exactly 200/121 m2 or about 1.653 m2, and that is the figure used here. A separate figure of 1.62 m2 is the minimum area per mat that Japanese property advertising rules allow when a room is described by its mat count, so it is a legal floor rather than a typical mat.

1 jō (tatami mat) = 1.652892562 square meters (approximately).

Sources: Wikipedia: Japanese units of measurement; Wikipedia: Tatami; Real Estate Tokyo: Units used for real estate size in Japan

Square Mile (mi²)

US & ImperialCurrent unit

640 acres or about 2.59 km². Used for the area of cities, states and countries in the US and UK.

A thousand Roman paces, mille passus, became the mile, and under Elizabeth I Parliament fixed the statute mile at eight furlongs, or 5,280 feet, in place of the older Roman-based value. The square mile inherits that length. Its most famous use came in the United States: the Land Ordinance of 1785 started the Public Land Survey System so that western land could be surveyed and sold to pay war debts, beginning with the Seven Ranges in eastern Ohio.

In that system a section is roughly one square mile, or 640 acres, and a township is 36 sections in a square six miles on a side. One square mile is nearly 2.59 million square meters. Chicago's Midway International Airport, at about 650 acres, covers roughly 1.02 square miles. Beware the phrase mile square: a region 20 miles square has 400 square miles, but so does a rectangle 10 by 40 miles. The US survey version of the mile was retired from 1 January 2023, but the international square mile remains the unit for cities, states and countries in the US and UK.

1 square mile = 2,589,988.11 square meters (approximately).

Sources: Wikipedia: Square mile; Wikipedia: Public Land Survey System; Wikipedia: Mile

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