How Many Square Feet in an Acre?
An acre is 43,560 square feet, or about 4,047 square metres. Here is where that number comes from, how big an acre actually looks, and a table for the common fractions of an acre you see on lot listings.
By the Calculate My Reno Team / Published
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An acre is 43,560 square feet. That is the number to remember; everything else is built from it:
1 acre = 43,560 sq ft
= 4,046.86 m²
= 4,840 sq yd
= 0.4047 hectares
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Enter a lot in the square footage calculator - even an irregular one, built from rectangles and triangles - and it shows the size in acres alongside square feet, square metres and square yards. The rest of this guide is the conversions and what an acre actually looks like.
Where 43,560 comes from
An acre was originally one chain by one furlong - the area a team of oxen could plough in a day. A chain is 66 ft and a furlong is 660 ft, so:
66 ft × 660 ft = 43,560 sq ft
The number looks arbitrary because the units behind it are medieval, but it is exact.
How big is an acre?
- As a square, an acre is about 208 ft × 208 ft.
- It is close to 90% of an American football field without the end zones (the full field including end zones is about 1.32 acres).
- It is roughly 16 tennis courts, or about 9 basketball courts.
An acre is just an amount of area - it can be any shape, long and thin or square.
Common fractions of an acre
| Lot size | Square feet | Square metres |
|---|---|---|
| 1/8 acre | 5,445 sq ft | 506 m² |
| 1/4 acre | 10,890 sq ft | 1,012 m² |
| 1/3 acre | 14,520 sq ft | 1,349 m² |
| 1/2 acre | 21,780 sq ft | 2,023 m² |
| 3/4 acre | 32,670 sq ft | 3,035 m² |
| 1 acre | 43,560 sq ft | 4,047 m² |
| 2 acres | 87,120 sq ft | 8,094 m² |
| 5 acres | 217,800 sq ft | 20,234 m² |
Square feet to acres
Divide by 43,560:
| Square feet | Acres |
|---|---|
| 5,000 sq ft | 0.11 acres |
| 10,000 sq ft | 0.23 acres |
| 20,000 sq ft | 0.46 acres |
| 43,560 sq ft | 1 acre |
| 100,000 sq ft | 2.30 acres |
Worked example
A rectangular building lot 150 ft by 200 ft:
150 × 200 = 30,000 sq ft
30,000 ÷ 43,560 = 0.69 acres
So just over two-thirds of an acre. To picture a smaller area, see how big is 1,000 square feet; to convert the figure to metric, square feet to square metres.
Frequently asked questions
How many square feet are in an acre?
An acre is exactly 43,560 square feet. It is also about 4,047 square metres, 4,840 square yards, or 0.405 of a hectare. The odd number comes from the old definition of an acre as one chain by one furlong, which is 66 ft by 660 ft.
How big is an acre visually?
Pictured as a square, an acre is roughly 208 feet on each side. It is close to 90% of an American football field without the end zones, or about 16 tennis courts. An acre does not have to be square - it is just a quantity of area, any shape.
How many square feet is half an acre?
Half an acre is 21,780 square feet (43,560 ÷ 2). A quarter acre is 10,890 square feet, and a tenth of an acre is 4,356 square feet. Lot listings often use these fractions, so the table below converts the common ones.
How do I convert square feet to acres?
Divide the square feet by 43,560. A 10,000 sq ft lot is 10,000 ÷ 43,560 = 0.23 acres. To go the other way, multiply acres by 43,560: 2 acres is 87,120 square feet.
How many square metres are in an acre?
An acre is about 4,047 square metres, or 0.4047 hectares. So a hectare, at 10,000 square metres, is about 2.47 acres. To convert a lot in square metres to acres, divide by 4,047.