Acres to Square Miles Converter
Enter the area in acres below to convert it to square miles.
Result in Square Miles:
Do you want to convert square miles to acres?
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How to Convert Acres to Square Miles
To convert a measurement in acres to a measurement in square miles, divide the area by the following conversion ratio: 640 acres/square mile.
Since one square mile is equal to 640 acres, you can use this simple formula to convert:
square miles = acres ÷ 640
The area in square miles is equal to the area in acres divided by 640.
For example, here's how to convert 500 acres to square miles using the formula above.
square miles = (500 ac ÷ 640) = 0.78125 sq mi
Acres and square miles are both units used to measure area. Keep reading to learn more about each unit of measure.
What Is an Acre?
One acre is defined as the area equal to a space that is one chain (66 ft) by one furlong (660 ft), or 10 square chains.[1] That's equal to 43,560 square feet or 1/640 of a square mile for those unfamiliar with those units of measure.
The acre is a US customary and imperial unit of area. Acres can be abbreviated as ac; for example, 1 acre can be written as 1 ac.
You can use an acreage calculator to measure the area of a plot of land in acres by locating the boundaries on a map.
Learn more about acres.
What Is a Square Mile?
One square mile is equal to the area of a square with sides that are each 1 mile long. One square mile is roughly equal to 2.59 square kilometers or 640 acres.
The square mile is a US customary and imperial unit of area. Square miles can be abbreviated as sq mi, and are also sometimes abbreviated as mi². For example, 1 square mile can be written as 1 sq mi or 1 mi².
Learn more about square miles.
Acre to Square Mile Conversion Table
| Acres | Square Miles |
|---|---|
| 1 ac | 0.001563 sq mi |
| 2 ac | 0.003125 sq mi |
| 3 ac | 0.004688 sq mi |
| 4 ac | 0.00625 sq mi |
| 5 ac | 0.007813 sq mi |
| 6 ac | 0.009375 sq mi |
| 7 ac | 0.010938 sq mi |
| 8 ac | 0.0125 sq mi |
| 9 ac | 0.014063 sq mi |
| 10 ac | 0.015625 sq mi |
| 20 ac | 0.03125 sq mi |
| 30 ac | 0.046875 sq mi |
| 40 ac | 0.0625 sq mi |
| 50 ac | 0.078125 sq mi |
| 60 ac | 0.09375 sq mi |
| 70 ac | 0.109375 sq mi |
| 80 ac | 0.125 sq mi |
| 90 ac | 0.140625 sq mi |
| 100 ac | 0.15625 sq mi |
| 200 ac | 0.3125 sq mi |
| 300 ac | 0.46875 sq mi |
| 400 ac | 0.625 sq mi |
| 500 ac | 0.78125 sq mi |
| 600 ac | 0.9375 sq mi |
| 700 ac | 1.0938 sq mi |
| 800 ac | 1.25 sq mi |
| 900 ac | 1.4063 sq mi |
| 1,000 ac | 1.5625 sq mi |
References
- National Institute of Standards and Technology, Specifications, Tolerances, and Other Technical Requirements for Weighing and Measuring Devices, Handbook 44 - 2019 Edition, https://nvlpubs.nist.gov/nistpubs/hb/2019/NIST.HB.44-2019.pdf