Square Feet to Acres Converter
1 acre = 43,560 square feet. To convert square feet to acres, divide by 43,560. Example: 87,120 sq ft ÷ 43,560 = 2 acres.
Inverse conversion
1 acre = 43,560 square feet. Multiply acres by 43,560 to convert. Example: 2.5 acres × 43,560 = 108,900 sq ft.
Formula
Formula
acres = square feet ÷ 43,560
Worked example
To convert 21,780 sq ft to acres: 21,780 ÷ 43,560 = 0.5 acres (half an acre).
Quick reference table
| ft² | ac |
|---|---|
| 1000 | 0.022957 |
| 5000 | 0.114784 |
| 10000 | 0.229568 |
| 21780 | 0.5 |
| 43560 | 1 |
| 87120 | 2 |
| 130680 | 3 |
| 217800 | 5 |
Unit definitions
Square Foot (ft²)
The square foot (ft²) is the area of a square with sides of 1 foot each. 1 ft² = 0.0929 m². Commonly used for room and property areas in the US.
Acre (ac)
The acre (ac) is a unit of area equal to 43,560 square feet or 4,046.86 m². Widely used for land measurement in the US and UK.
Common use cases
- Real estate land area
- Farm and agricultural land
- Zoning and land permits
- Property appraisal