An acre (symbol: ac) is a unit of area commonly used in land measurement, especially in agriculture, real estate, and surveying. One acre equals 43,560 square feet, which can be expressed with MathJax as \\(1\\,\\text{ac}=43,560\\,\\text{ft}^2\\).
A square foot (symbol: ft²) is a smaller unit of area used for interior spaces, flooring, and construction projects. It represents the area of a square with sides one foot long.
Practical Applications
Farmers calculate field sizes in acres to estimate crop yields.
Real‑estate agents list property parcels in acres for large lots.
Architects and contractors use square feet to design floor plans and estimate material quantities.
Urban planners convert acres to square feet when integrating large green spaces into city grids.
Because the conversion factor is constant, converting between these units is straightforward: multiply the number of acres by 43,560 to obtain the equivalent area in square feet.
Acre to Square foot Conversion Reference Table
Acre (ac)
Square foot (ft²)
0.1
4356
0.5
21780
1.0
43560
2.0
87120
5.0
217800
10.0
435600
20.0
871200
50.0
2.1780e+06
100.0
4.3560e+06
500.0
2.1780e+07
1000.0
4.3560e+07
Step‑by‑Step Conversion Example
Convert 10 acres to square feet.
Identify the conversion factor: \(1\,\text{ac}=43,560\,\text{ft}^2\).
The acre persists because many land‑related industries (agriculture, real estate, and surveying) have long‑standing conventions and legal documents expressed in acres. Transitioning to metric units would require extensive re‑education and amendment of contracts, so the acre remains practical in those contexts.
The factor 43,560 ft² per acre is exact by definition. It originates from the historical definition of an acre as a rectangle 66 ft by 660 ft, yielding 66 × 660 = 43,560 ft². Therefore, the conversion is precise with no rounding error.
"On fait la science avec des faits, comme on fait une maison avec des pierres ; mais une accumulation de faits n'est pas plus une science qu'un tas de pierres n'est une maison." "Science is built up of facts, as a house is built of stones; but an accumulation of facts is no more a science than a heap of stones is a house." — Henri Poincaré (French Mathematician, Theoretical Physicist & Mining Engineer)