Square Miles to Chō (area) (mi² to chō)

1 square mile equals 261.1571345 chō (area) (rounded).

1 square mile = 261.1571345 chō (area)

How to convert square miles to chō (area)

To convert square miles to chō (area), multiply the number of square miles by 261.1571345. The factor is rounded to 10 significant digits. To go the other way, multiply chō (area) by 0.003829112316 (rounded).

chō (area) = square miles × 261.1571345

Example: 10 square miles = 2,611.571345 chō (area).

About these units

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

Chō (area) (chō)

JapaneseTraditional unit (still used in some regions)

3,000 tsubo, about 9,917 m² (roughly one hectare; 2.45 acres). Used for farmland in Japan.

Almost exactly a hectare, the cho is the largest of the everyday Japanese land units. It is 3,000 tsubo, or 1,200,000/121 square metres, about 9,917, which is 0.9917 hectare or roughly 2.45 acres. It is also 100 se or 10 tan, and when no fractional part follows it is often written cho-bu.

Because it is so near a hectare, it is a convenient mental bridge for anyone moving between traditional and metric figures. In Japan it has been used for farmland, and it sits at the top of the tsubo, se and tan ladder.

The name is shared with a unit of length, so the area sense needs to be stated. The area figure used here follows from the 10/33 metre shaku fixed by the 1891 Meiji law, and the 1951 Measurements Law took the traditional units out of official use from 1959.

1 chō (area) = 9,917.355372 square meters (approximately).

Sources: Wikipedia: Japanese units of measurement; Wikipedia: Shaku (unit); Wikipedia: Tsubo

Related conversions

See all area units.