Square Feet to Acres Calculator
Listings quote square feet, deeds quote acres, and the rest of the world uses hectares, so you end up converting more than you'd think. Enter an amount, pick the unit it's in, and get every other unit back at once. It works both ways: square feet to acres, acres to square feet, or anything to hectares.
Square feet to acres, both directions
Real estate listings talk in square feet, deeds and rural land talk in acres, and you end up converting between them more than you'd think. This tool goes both ways, square feet to acres and back, and shows hectares and square meters too. Type a number, get the answer, see the division that produced it.
The conversion
One acre is exactly 43,560 square feet. To go from square feet to acres, divide by 43,560. To go the other way, multiply acres by 43,560. That's the whole thing. Half an acre is 21,780 square feet; a quarter acre is 10,890.
Where 43,560 comes from
The number isn't random. An acre was once a day's plowing for a team of oxen, set as a strip one chain wide by one furlong long. A chain is 66 feet and a furlong is 660, and 66 times 660 is 43,560. The odd figure is a leftover from medieval farming that the US never rounded off.
Common conversions both ways
| Square feet | Acres |
|---|---|
| 5,000 | 0.115 |
| 7,500 | 0.172 |
| 10,000 | 0.230 |
| 21,780 | 0.500 |
| 43,560 | 1.000 |
| 87,120 | 2.000 |
A worked conversion
Say a listing reads 10,000 square feet. Divide 10,000 by 43,560 and you get 0.2296, so about 0.23 acre, a hair under a quarter acre. Go the other way and a half-acre listing is 0.5 times 43,560, or 21,780 square feet. The tool shows that division so the number isn't a black box.
When this conversion comes up
City and suburban lots get sold in square feet because the numbers are tidy at that scale. Rural and agricultural land gets sold in acres because the parcels are large. The moment you compare a suburban lot to a few acres in the country, you have to put both in the same unit first, which is exactly what this does. To size an odd lot from its dimensions, use the acreage calculator.
Common questions
43,560 square feet. It's a fixed conversion, so an acre is always 43,560 square feet whether the land is square, rectangular, or irregular.
Divide the square footage by 43,560. So 21,780 square feet is half an acre. The calculator above does it and shows hectares and square yards too.
Multiply acres by 43,560. Two acres is 87,120 square feet. Set the From unit to acres above and the tool flips the conversion.
It comes from old English land measure: an acre was one chain (66 feet) by one furlong (660 feet), which is 43,560 square feet. The odd number stuck.
Estimates for planning. Verify against your supplier's units and your local building codes before ordering or building. For anything structural, follow your engineer or local code.