How it's calculated
acres = area(ft²) ÷ 43,560
area = parcel area in square feet — rectangle L × W, circle π × r², or triangle ½ × base × height (inputs first converted to feet). 43,560 ft² = 1 acre.
Common questions
How big is an acre?
An acre is 43,560 square feet, a little smaller than a standard American football field.
How many acres is a typical house lot?
Many suburban lots fall between about 0.1 and 0.5 acre, though rural parcels can be much larger.