Acre is a unit used to measure land area in the imperial and US customary systems. It equals 43,560 square feet and 4046.86 square meters. The acre is a common measurement for large areas like forests, farmland, fields, cities. The word originates from Old English æcer which means "open field". 1 acre is about 90 % of the American football field. You can convert Acres to other units here by enter amount of if into green input below. You can also check some basic conversions in Acres Conversion Table.