Square feet to acres, a sq ft to acreage calculator.

To convert square feet to acres, divide the area by 43,560. That is the whole rule, because one acre is exactly 43,560 square feet. A lot of 10,000 sq ft is 0.22957 acres, a lot of 5,000 sq ft is 0.11478 acres, and 21,780 sq ft is exactly half an acre. If you have a length and width instead of an area, multiply them first, then divide.

How to use the calculator

1. Type the area in the Square feet (ft²) box. The page opens on 10,000 sq ft.
2. Read the acres in the big result. The cards show the same area in square meters, hectares and square yards.
3. If you only know the sides of the lot, multiply length by width in feet first. A lot 150 ft by 200 ft is 30,000 sq ft, which is 0.6887 acres. Then type 30000.
4. Choose Decimals: 2 for a listing, 4 or more for a survey sum. Copy result and Copy link share it, and Print chart gives a sheet of lot sizes.
5. Press the swap button (or S) to go from acres to square feet.

The numbers an acre is made of

NIST Handbook 44 (2026), Appendix C (checked 26 Oct 2026) gives one acre as 43,560 square feet, 4,840 square yards and 4,046.856 422 4 square meters, using the international foot. It adds that an acre does not have to be a square: if it were, each side would be about 208.710 ft, the square root of 43,560. A square mile is 640 acres.

The same Handbook explains that the US survey foot was retired at the end of 2022, and gives a separate survey acre of 4,046.872 609 874 m². The two acres differ by about 0.0004 percent, which is 17 sq ft in 100 acres. This calculator uses the international acre. The difference is far below the size that matters for a house lot.

Lot size examples

These show the sum, not what any town allows. Width times depth is the area, and the area divided by 43,560 is the acreage.

An American football field with its end zones, 360 ft by 160 ft in the NFL Official Playing Rules (2025 edition) (read 26 Oct 2026), covers 57,600 sq ft, which is 1.3223 acres. A whole acre is about 208.7 ft by 208.7 ft if you want to picture it square, or 66 ft by 660 ft if you want to picture it long.

Handy fractions of an acre

Worked examples

• 7,500 sq ft. 7,500 ÷ 43,560 = 0.1722 acres.
• 12,000 sq ft. 0.2755 acres.
• 30,000 sq ft. 0.6887 acres.
• 100,000 sq ft. 2.296 acres.
• 1,000,000 sq ft. 22.96 acres.

Metric lots and other units

If a lot is given in square meters, divide by 4,046.8564224 to get acres, since that is the exact size of one acre in square meters. A 600 m² lot is then 0.1483 acres and a 1,000 m² lot is 0.2471 acres. A hectare is 10,000 m², which is 2.4711 acres. The cards under the result give square meters and hectares for any area you type.

Reading a listing

Listings round. A lot shown as "0.23 acres" could be anything from 9,801 sq ft to 10,237 sq ft, the sizes that round to 0.23. If you need the exact size, look for the square feet on the plat or the deed, and convert it here with four or five decimals.

Common mistakes

The first is mixing linear and square units. A lot that is 43,560 feet long is not an acre, and an acre is not 43,560 feet on a side. The second is dividing a length given in yards or meters by 43,560 without turning it into feet first. The third is rounding the factor to 43,000 or 44,000, which shifts the acreage by 1 to 2 percent.

Odd shapes

For a rectangle, multiply the sides. For a triangle take half of base times height. For anything else, split the lot into rectangles and triangles, add the areas in square feet, then convert the total. The square footage calculator does the adding for several rooms or parcels.

The reverse is on acres to square feet, and bigger areas are on square miles to acres.