Convert acres to square miles
Enter the number of acres that you want to convert to square miles.
How to Convert Acres to Square Miles
The acre and square mile are both units of area. By definition, 1 square mile equals exactly 640 acres. This means to convert acres to square miles, you divide by 640.
Formula
Step-by-Step Example
Convert 5 acre to square miles:
We need to convert acres to square miles
Since 1 mi² = 640 acre, divide by 640
5 ÷ 640 = 0.0078125
5 acre = 0.0078125 mi²
Acre to Square Mile Conversion Table
Quick reference table for common acre to square mile conversions. Click any value for detailed calculation.
| Acres (acre) | Square Miles (mi²) |
|---|---|
| 0.1 acre | 0.00015625 mi² |
| 0.5 acre | 0.00078125 mi² |
| 1 acre | 0.0015625 mi² |
| 2 acre | 0.003125 mi² |
| 5 acre | 0.0078125 mi² |
| 10 acre | 0.015625 mi² |
| 25 acre | 0.0390625 mi² |
| 50 acre | 0.078125 mi² |
| 100 acre | 0.15625 mi² |
About These Units
Acre (acre)
An acre equals 43,560 square feet, 4,047 square meters, or approximately 0.405 hectares. Acres are the standard land measurement in the US and UK for farms, lots, and real estate. An American football field (without end zones) is about 1.1 acres. One square mile contains 640 acres.
Square Mile (mi²)
A square mile (mi² or sq mi) equals 640 acres, 2.59 square kilometers, or 27,878,400 square feet. Square miles measure city sizes, counties, and states in the US. Manhattan is about 23 square miles. One section of land (US survey) equals one square mile.
Frequently Asked Questions
How do I convert acres to square miles?
To convert acres to square miles, divide the value by 640. For example, 10 acre = 0.015625 mi².
How many square miles are in 1 acre?
1 acre equals 0.0015625 square miles.
What is the formula for acres to square miles?
The formula is: mi² = acre ÷ 640.