An are is 100 square meters.
Ares to Square miles Converter — a to mi2
Convert Are (a) to Square mile (mi2) using the exact conversion factor (1 are = 0.0000386102 square mile). See the formula, worked examples, conversion table, history, and common uses.
Ares to Square miles converter
Converter
Area Converter
Convert land, construction, mapping, survey, and scientific area units.
Context values
Some unit families need one extra value for a physically accurate result.
A square mile is 640 acres.
Result = input x 100 / 2.58998811e+6.
Area uses the square meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Ares to Square miles
Comparing Are and Square mile is common in agriculture and real estate, where US land is typically measured in acres and most of the rest of the world uses hectares. Specifically: An are is 100 square meters, and a square mile is 640 acres.
Formula
square miles = ares × 0.0000386102158542
This factor comes from each unit's defined relationship to the category's base unit: 1 are equals 100 base units, and 1 square mile equals 2589988.11034 base units, so dividing one by the other gives the direct are-to-square mile factor of 0.0000386102158542.
Simple example
1 a × 0.00003861021585 = 0.0000386102 mi2
1 are = 0.0000386102 square miles.
Real-world example
10 a × 0.00003861021585 = 0.0003861022 mi2
10 ares = 0.0003861022 square miles.
Conversion table
| Are (a) | Square mile (mi2) |
|---|---|
| 1 a | 0.0000386102 mi2 |
| 5 a | 0.0001930511 mi2 |
| 10 a | 0.0003861022 mi2 |
| 25 a | 0.0009652554 mi2 |
| 50 a | 0.0019305108 mi2 |
| 100 a | 0.0038610216 mi2 |
Reverse conversion: Square mile to Are
0.0000386102 mi2 × 25899.8811 = 0.9999995894 a
0.0000386102 square miles = 0.9999995894 ares.
ares = square miles × 25899.8811034
For a page dedicated to this direction, see Square mile to Are.
Understanding the Are (a)
An are is 100 square meters.
Understanding the Square mile
Square mile (mi2) measures area. A square mile is exactly 2,589,988.110336 square meters, derived from the international mile fixed in 1959. It is classified as a US/imperial customary unit.
Where it's used: United States (county, metro, and regional area reporting)
Uses of the Square mile today
- US city, county, and regional area statistics
- Population density reporting (people per square mile)
- Land-use and geography in US contexts
History of the Square mile
The square mile follows directly from the statute mile, itself fixed at exactly 1,609.344 meters by the 1959 International Yard and Pound Agreement; squaring that value gives the modern square mile.
Historical origin. Square mile was not the invention of a single named person; it developed through the process described above.
Square mile — sources
- NIST — International yard and pound (1959) — Basis for the modern mile and its derived area unit.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many square miles are in 1 are?
1 are equals 0.0000386102 square miles, using the exact defined conversion factor rather than an estimate.
How do I convert are to square mile?
Multiply the are value by 0.00003861021585. The converter above does this instantly to whatever precision you set.
How do I convert square mile back to are?
Use the reverse factor: 1 square mile equals 25,899.8811 ares. You can also use the swap control in the converter above to flip the direction instantly.
What is a are?
Are (a) is a unit of area.
What is a square mile?
Square mile (mi2) measures area. A square mile is exactly 2,589,988.110336 square meters, derived from the international mile fixed in 1959. It is classified as a US/imperial customary unit.
Is the are to square mile conversion exact?
Yes. A square mile is exactly 2,589,988.110336 square meters, derived from the international mile fixed in 1959. That fixed definition is what the converter above uses, so any rounding you see is a display choice, not a limitation of the math.