Square miles to Acres Converter
Convert square miles (sq mi) to acres (ac) instantly. Area conversions are everyday maths in Singapore property: HDB flats are listed in square metres while condo listings and PSF prices use square feet.
Result
- Acres
- 640 ac
How to use the square miles to acres converter
- Enter the square miles (sq mi).
- The results update as you type, or press Calculate.
- Read the acres first, then the supporting figures below it.
Formula
Acres = square miles × 640
Worked example
For example, with these inputs:
- Square miles (sq mi): 1
the calculator returns:
- Acres: 640 ac
Square miles to Acres table
| Square miles | Acres |
|---|---|
| 1 sq mi | 640 ac |
| 2 sq mi | 1,280 ac |
| 5 sq mi | 3,200 ac |
| 10 sq mi | 6,400 ac |
| 20 sq mi | 12,800 ac |
| 25 sq mi | 16,000 ac |
| 50 sq mi | 32,000 ac |
| 100 sq mi | 64,000 ac |
| 250 sq mi | 160,000 ac |
| 500 sq mi | 320,000 ac |
| 1,000 sq mi | 640,000 ac |
About this conversion
Area conversions are everyday maths in Singapore property: HDB flats are listed in square metres while condo listings and PSF prices use square feet.
Many conversion factors are exact by definition. The inch has been defined as exactly 2.54 centimetres since 1959, and the pound as exactly 0.45359237 kilograms, so conversions involving them can be as precise as you need.
Singapore adopted the metric system in the 1970s, replacing imperial units and traditional Chinese measures in most official uses. Metric units are now standard in schools, trade and government, but older units survive in property, markets and imported goods.
Frequently asked questions
How many acres are in one square mile?
1 sq mi = 640 ac.
How do I convert sq mi to ac?
Acres = square miles × 640.