Convert square miles to acres
1 mi² = 640 ac. Change the amount below, or read the formula and the reference table further down.
1 square mile equals
acres
1 mi² = 640 ac
The formula
Square miles and acres both measure area from the same zero, so a single multiplier does the job.
ac = mi² × 640
Going the other way? Convert acres to square miles.
Square miles to acres table
Common values, rounded for reading.
| Square miles (mi²) | Acres (ac) |
|---|---|
| 1 | 640 |
| 2 | 1,280 |
| 3 | 1,920 |
| 4 | 2,560 |
| 5 | 3,200 |
| 6 | 3,840 |
| 7 | 4,480 |
| 8 | 5,120 |
| 9 | 5,760 |
| 10 | 6,400 |
| 15 | 9,600 |
| 20 | 12,800 |
| 25 | 16,000 |
| 30 | 19,200 |
| 40 | 25,600 |
| 50 | 32,000 |
| 75 | 48,000 |
| 100 | 64,000 |
| 250 | 160,000 |
| 500 | 320,000 |
| 1,000 | 640,000 |
Questions people ask
- How many acres are in a square mile?
- One square mile equals 640 acres.
- How do I convert square miles to acres by hand?
- Multiply the number of square miles by 640. For a rough check, 640 is close enough for most everyday use.
- What is 1 square mile in acres?
- 1 square mile is 640 acres.
Calcuit generates this page from a unit table, so the factors here match every other page on the site.