Unit converter
Acres to Square Feet Converter
An acre contains exactly 43,560 square feet, a figure that falls out of the old definition of one chain by one furlong (66 ft by 660 ft).
1 acre = 43,560 square feet
Common acres to square feet values
| Acres | Square feet |
|---|---|
| 1 ac | 43,560 ft² |
| 2 ac | 87,120 ft² |
| 5 ac | 217,800 ft² |
| 10 ac | 435,600 ft² |
| 20 ac | 871,200 ft² |
| 50 ac | 2,178,000 ft² |
| 100 ac | 4,356,000 ft² |
Enter an area in acres and this tool returns the equivalent in square feet, with a table for the sizes people check most often. Surveyors, estate agents and farmers reach for this when a plot is sold by the acre but quoted in square feet, when working out how many house lots fit on a field, or when comparing a sports pitch against a building footprint.
How to convert
- Start with the area measured in acres.
- Multiply by 43,560, since a single acre equals exactly 43,560 square feet.
- The product is that same area written in square feet.
- Reverse the process by dividing a square-foot figure by 43,560 to recover acres.
- For a rough head count, treat one acre as roughly 44,000 square feet, then trim a little.
square feet = acres × 43,560
The acre is defined as 4,840 square yards, and each square yard holds 9 square feet, so an acre is 4,840 times 9, which is 43,560 square feet. Multiplying acres by that constant gives square feet; dividing reverses it.
- ac
- the area in acres you begin with
- 43,560
- square feet in one acre, by definition
Worked example
A 5-acre paddock comes to 5 times 43,560, which is 217,800 square feet. Half an acre, by the same logic, is 21,780 square feet, close to the footprint of a small supermarket.
Key facts
- One acre equals exactly 43,560 square feet.
- An acre is also 4,840 square yards or 1/640 of a square mile.
- A square mile (a section) packs 640 acres, hence 27,878,400 square feet.
- A quarter-acre building plot is 10,890 square feet.
Tips
- For quick sums, remember a tenth of an acre is 4,356 square feet.
- When dividing land into lots, work in square feet first, then convert the total back to acres at the end.
Frequently asked questions
How many square feet are in 1 acre?+
Exactly 43,560 square feet. The number is fixed because the acre is defined from the square yard, with no rounding involved.
Where does 43,560 come from?+
An acre was historically a chain (66 ft) by a furlong (660 ft). Multiplying 66 by 660 gives 43,560 square feet.
How big is an acre in plain terms?+
Picture a square about 209 ft on each side, or a touch smaller than a standard football pitch including the surround.
Is a US acre the same as a UK acre?+
Yes. Both rest on the international yard fixed in 1959, so an acre is 43,560 square feet in either country.
Things to watch
- Acreage on old deeds may use the pre-1959 US survey foot; the difference is tiny but can matter on very large parcels.
Sources
Last updated: 2026-01-01
Conversions use internationally defined factors. Provided for general use; verify critical measurements independently.