Acres to square miles converter
Square miles (mi²)
1 acre = 0.0015625 square miles
How to convert acres to square miles
mi² = ac × 0.0015625
Multiply the number of acres by 0.0015625 to get square miles. Going the other way, divide by 0.0015625 (or multiply by 640).
One acre is exactly defined as 0.0015625 square miles (to 12 significant figures), and one square mile is 640 acres.
Worked examples
- Convert 5 acres: 5 × 0.0015625 = 0.0078125 0.0078125 square miles.
- Convert 12.5 acres: 12.5 × 0.0015625 = 0.01953125 0.01953125 square miles.
- Convert 250 acres: 250 × 0.0015625 = 0.390625 0.390625 square miles.
Quick-reference table
| ac | mi² |
|---|---|
| 1 | 0.0015625 |
| 2 | 0.003125 |
| 3 | 0.0046875 |
| 5 | 0.0078125 |
| 10 | 0.015625 |
| 15 | 0.0234375 |
| 20 | 0.03125 |
| 25 | 0.0390625 |
| 50 | 0.078125 |
| 75 | 0.1171875 |
| 100 | 0.15625 |
| 1,000 | 1.5625 |
| mi² | ac |
|---|---|
| 1 | 640 |
| 2 | 1,280 |
| 3 | 1,920 |
| 5 | 3,200 |
| 10 | 6,400 |
| 15 | 9,600 |
| 20 | 12,800 |
| 25 | 16,000 |
| 50 | 32,000 |
| 75 | 48,000 |
| 100 | 64,000 |
| 1,000 | 640,000 |
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Frequently asked questions
How many square miles are in 1 acre?
1 acre equals 0.0015625 square miles.
What is the formula to convert acres to square miles?
Use mi² = ac × 0.0015625. Multiply the number of acres by 0.0015625 to get square miles. Going the other way, divide by 0.0015625 (or multiply by 640).
What is 100 acres in square miles?
100 acres is 0.15625 square miles.