Square foot

The square foot (plural square feet; abbreviated ft² or sq ft) is an imperial unit and U.S. customary unit of area, used mainly in the United States, Canada, United Kingdom, Hong Kong, Bangladesh, India, Pakistan and Afghanistan. It is defined as the area of a square with sides of 1 foot in length. For comparison, the average new one-family house in the United States in 2007 had a total floor area of approximately 2500 square feet (232 square meters).