How many acres are in a square foot?

1 ft² = 2.2957e-5 ac. To convert any amount, multiply by 2.2957e-5.

How do you convert square feet to acres?

Multiply the number of square feet by 2.2957e-5 to get acres. The formula is shown in the "How it's calculated" section above.

Where does the conversion factor come from?

It's a published international standard. Most are defined exactly by international agreement (e.g. 1 inch = 25.4 mm exactly, 1 lb = 0.45359237 kg exactly). Source citations are listed under the formula above.

Unit converter — Area

Square feet to acres converter

Convert square feet (ft²) to acres (ac). Source-cited conversion factor, exact to the displayed precision.

Results are mathematically exact for the displayed precision. How we calculate.

How it's calculated

Convert square feet to acres— the formula

Square feet convert to acres by multiplying by the published conversion factor. The factor below is exact to the precision shown, sourced from the citation under the formula.

ac = ft² × 2.2957e-5

ft² = ac × 43560

Derived from the length conversion factors. 1 acre = 4046.8564224 m² (international acre, 43560 ft²).

Questions

Frequently asked questions

How many acres are in a square foot?
1 ft² = 2.2957e-5 ac. To convert any amount, multiply by 2.2957e-5.
How do you convert square feet to acres?
Multiply the number of square feet by 2.2957e-5 to get acres. The formula is shown in the "How it's calculated" section above.
Where does the conversion factor come from?
It's a published international standard. Most are defined exactly by international agreement (e.g. 1 inch = 25.4 mm exactly, 1 lb = 0.45359237 kg exactly). Source citations are listed under the formula above.