Acre/ˈeɪkər/ Definition 1 of 3Pro Tip 1/3Land Measurement An acre is commonly used to measure large tracts of land, like farms. The new solar farm will cover a hundred acres. Pro Tip 2/3Visualizing Size Since an acre is a large area, compare it to football fields for better understanding. Two football fields are slightly larger than an acre. Pro Tip 3/3Conversion Factor Remember, one acre is about 0.4047 hectares or 4,840 square yards. The agricultural land was 5 hectares, or about 12.35 acres.