Acres to Square Miles
Convert acres (ac) to square miles (mi²). Type in either box; the other updates as you go.
1 acre equals0.0015625 mi²
1 square mile equals640 ac
Formulami² = ac ÷ 640
How to convert acres to square miles
To convert acres to square miles, divide the number of acres by 640.
mi² = ac ÷ 640
Example
Convert 5 acres to square miles:
5 ac ÷ 640 = 0.0078125 mi²
Acre to square mile conversion chart
| Acres (ac) | Square Miles (mi²) |
|---|---|
| 1 ac | 0.0015625 mi² |
| 2 ac | 0.003125 mi² |
| 3 ac | 0.0046875 mi² |
| 4 ac | 0.00625 mi² |
| 5 ac | 0.0078125 mi² |
| 6 ac | 0.009375 mi² |
| 7 ac | 0.0109375 mi² |
| 8 ac | 0.0125 mi² |
| 9 ac | 0.0140625 mi² |
| 10 ac | 0.015625 mi² |
| 12 ac | 0.01875 mi² |
| 15 ac | 0.0234375 mi² |
| 20 ac | 0.03125 mi² |
| 25 ac | 0.0390625 mi² |
| 30 ac | 0.046875 mi² |
| 40 ac | 0.0625 mi² |
| 50 ac | 0.078125 mi² |
| 60 ac | 0.09375 mi² |
| 70 ac | 0.109375 mi² |
| 75 ac | 0.1171875 mi² |
| 80 ac | 0.125 mi² |
| 90 ac | 0.140625 mi² |
| 100 ac | 0.15625 mi² |
| 150 ac | 0.234375 mi² |
| 200 ac | 0.3125 mi² |
| 250 ac | 0.390625 mi² |
| 500 ac | 0.78125 mi² |
| 1,000 ac | 1.5625 mi² |
Going the other way? See the square miles to acres chart.
About the units
Acre (ac)
An acre is 43,560 square feet, about 4,047 square meters. US and UK land is measured in acres.
Square Mile (mi²)
A square mile is 640 acres, about 2.59 square kilometers.
Frequently asked questions
How many square miles are in an acre?
There are 0.0015625 square miles in an acre.
How many acres are in a square mile?
There are 640 acres in a square mile.
How do you convert acres to square miles?
To convert acres to square miles, divide the number of acres by 640.
What is 5 acres in square miles?
5 acres equals 0.0078125 square miles.
Convert between square feet, square meters, acres, hectares and other units of area. Open the area converter to see a value in every unit at once.