Acres to Square Feet Calculator

The conversion is straightforward: square feet = acres × 43,560. The factor 43,560 comes from the historical definition of an acre as the area of a rectangle measuring one chain (66 feet) by one furlong (660 feet). Multiply 66 × 660 and you get exactly 43,560. This relationship was standardized during the British Imperial system and carried forward into the US customary system without modification. The acre itself originates from the Latin word 'ager' (field), and the chain-and-furlong dimensions reflect the practical limits of pre-industrial ox-drawn plowing. Because the conversion factor is an exact integer, there is no rounding error: one acre is always precisely 43,560 ft², two acres is always 87,120 ft², and so on. For fractional acres such as 0.17 acres (a typical urban infill lot), simply multiply 0.17 × 43,560 to get 7,405.2 square feet. The result is presented to two decimal places to handle sub-square-foot precision when needed.