What this converter does
This tool converts an area measured in acres (ac) into square feet (ft², also written sf, sqft, or sq ft). It uses the exact international acre definition, where one acre equals 43,560 square feet. Just type the number of acres and you instantly get the equivalent area in square feet, along with a "Solution" line that shows the arithmetic.
The formula
The conversion is a single fixed-factor multiplication:
$$\text{square feet} = \text{acres} \times 43{,}560$$
The constant 43,560 comes from the historic definition of an acre as one chain by one furlong, which equals \(66\ \text{ft} \times 660\ \text{ft} = 43{,}560\ \text{ft}^2\). You can also write the same relationship in reciprocal form as \(\text{square feet} = \text{acres} \div 0.00002295684\), because one square foot is about 0.00002295684 of an acre.
How to use it
Enter the area in acres in the input box and the result updates with the equivalent in square feet, formatted with thousands separators. Decimals are supported, so 0.25 acres or 2.3 acres both work. To go the other way, divide your square footage by 43,560 to get acres.
Worked example
Suppose a plot of land is 2.3 acres. Multiply: $$2.3 \times 43{,}560 = 100{,}188\ \text{sq ft}.$$ As a second check, \(5\ \text{acres} \times 43{,}560 = 217{,}800\ \text{ft}^2\). A standard quarter-acre suburban lot is \(0.25 \times 43{,}560 = 10{,}890\ \text{ft}^2\).
Acres to Square Feet Conversion Table
One acre equals exactly 43,560 square feet, so any acreage can be converted to square feet by multiplying by that fixed factor:
$$\text{ft}^2 = \text{acres} \times 43{,}560$$The table below lists common acre values with their exact square-foot equivalents. Because the conversion factor is exact, every row is a precise figure, not a rounded estimate.
| Acres (ac) | Square Feet (ft²) |
|---|---|
| 0.1 | 4,356 |
| 0.25 | 10,890 |
| 0.5 | 21,780 |
| 1 | 43,560 |
| 2 | 87,120 |
| 2.3 | 100,188 |
| 5 | 217,800 |
| 10 | 435,600 |
| 40 | 1,742,400 |
| 160 | 6,969,600 |
| 640 | 27,878,400 |
Note that 640 acres equals one square mile (27,878,400 ft²), 160 acres is a quarter-section, and 40 acres is a quarter-quarter-section — all standard subdivisions in the U.S. Public Land Survey System.
FAQ
How many square feet are in an acre? Exactly 43,560 square feet for the international acre.
Does this use the US survey acre? No. It uses the international acre. The US survey acre differs by a factor of about 1.000004, which is negligible for everyday use.
How do I convert square feet back to acres? Divide the square footage by 43,560 (or multiply by 0.00002295684). For example, \(100{,}188 \div 43{,}560 = 2.3\) acres.
