Ares to Square Miles (a to mi²)
1 are equals 0.00003861021585 square miles (rounded).
How to convert ares to square miles
To convert ares to square miles, multiply the number of ares by 0.00003861021585. The factor is rounded to 10 significant digits. To go the other way, multiply square miles by 25,899.8811 (rounded).
square miles = ares × 0.00003861021585
Example: 10 ares = 0.0003861021585 square miles.
About these units
Are (a)
100 square meters, a square 10 m on a side. Mostly replaced by the hectare (100 ares).
Latin area, meaning an open piece of ground, gave French the word are, the base land unit of the metric system. A French law of 1795 defined it as 100 square meters, a square ten meters on each side, and the hectare was then built as 100 ares, which is why that familiar unit carries the "hecto-" prefix.
The are itself never made it into the modern SI when the system was rationalised in 1960, and the hectare took over for fields, forests and planning. The are survives mostly as a convenience for small plots such as building lots and gardens, and in everyday talk in parts of continental Europe. NIST lists it as exactly 100 square meters, so the figure used here is firm, and 100 ares make one hectare. The hectare is about 2.47 acres, so an are is roughly a fortieth of an acre.
1 are = 100 square meters (exactly).
Sources: Wikipedia: Hectare; NIST SP 811, Appendix B.8 conversion factors
Square Mile (mi²)
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
Related conversions
- Square miles to ares (reverse)
- Ares to square meters
- Ares to square kilometers
- Ares to hectares
- Ares to square inches
- Ares to square feet
- Ares to square yards
- Ares to acres
- Square meters to square miles
- Square kilometers to square miles
- Hectares to square miles
- Square inches to square miles
- Square feet to square miles
- Square yards to square miles
- Acres to square miles
- Square centimeters to square miles
- Square millimeters to square miles
- Tsubo to square miles
- Pyeong to square miles
- Rai (Thai) to square miles
See all area units.