Square Miles to Acres Converter
How to convert square miles to acres
acres = square miles × 640
To convert square miles to acres, multiply the number of square miles by 640.
1 mi² = 640 ac
Examples
- 640 acres: 1 mi² × 640 = 640 ac
- 100 mi² × 640 = 64,000 ac
Good to know
One square mile is exactly 640 acres.
This is the international acre. The US survey acre, based on the survey foot that was retired at the end of 2022, is about 4,046.873 m², a difference of roughly 4 parts per million.
Square miles to acres conversion table
| Square miles (mi²) | Acres (ac) |
|---|---|
| 1 mi² | 640 ac |
| 2 mi² | 1,280 ac |
| 3 mi² | 1,920 ac |
| 4 mi² | 2,560 ac |
| 5 mi² | 3,200 ac |
| 10 mi² | 6,400 ac |
| 15 mi² | 9,600 ac |
| 20 mi² | 12,800 ac |
| 25 mi² | 16,000 ac |
| 50 mi² | 32,000 ac |
| 75 mi² | 48,000 ac |
| 100 mi² | 64,000 ac |
| 200 mi² | 128,000 ac |
| 500 mi² | 320,000 ac |
| 1,000 mi² | 640,000 ac |
| 5,000 mi² | 3,200,000 ac |
| 10,000 mi² | 6,400,000 ac |
Unit definitions
- Square mile (mi²)
- A square mile is 640 acres, exactly 2,589,988.110336 square meters. It is used in the United States for the areas of cities, counties and states.
- Acre (ac)
- An acre is 43,560 square feet, exactly 4,046.8564224 square meters. It is the usual unit for land area in the United States and is still common in the United Kingdom.