The cubic foot (symbol ft3 or cu ft) is an imperial and US customary (non-metric) unit of volume, used in the United States and the United Kingdom. It is defined as the volume of a cube with sides of one foot (0.3048 m) in length. Its volume is 28.3168 L (about 1⁄35 of a cubic metre).

There are 12 inches in a foot therefore a cubic foot is 12 inches high by 12 inches wide by 12 inches depth. 1 cubic foot is (12 x 12 x12) = 1728 cubic inches.

A standard cubic foot (abbreviated scf) is a measure of quantity of gas, sometimes defined in terms of standard temperature and pressure as a cubic foot of volume at 60 degrees Fahrenheit (15.56 °C; 288.71 K) and 14.7 pounds per square inch (PSI) (1.01 bar; 101.35 kPa) of pressure.

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