The cubic foot (symbol ft<sup>3</sup> 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 () in length, or exactly (which is about 1% off of of a cubic metre, making that a suitable approximation in many cases).
The IEEE symbol for the cubic foot is ft<sup>3</sup>. The following abbreviations are used: cubicfeet, cubicfoot, cubicft, cufeet, cufoot, cuft, cu.ft, cuft, cbft, cb.ft, cbft, cbf, feet, foot, ft, feet/-3, foot/-3, ft/-3.
Larger multiples are in common usage in commerce and industry in the United States:
The IEEE symbol for the cubic foot per second is ft<sup>3</sup>/s. The following other abbreviations are also sometimes used:
The flow or discharge of rivers, i.e., the volume of water passing a location per unit of time, is commonly expressed in units of cubic feet per second or cubic metres per second.
Cusec is a unit of flow rate, used mostly in the United States in the context of water flow, particularly of rivers and canals.
Conversions: 1 ft<sup>3</sup>/s = = = =
The IEEE symbol for the cubic foot per minute is ft<sup>3</sup>/min. The following abbreviations are used:
Cubic feet per minute is used to measure the amount of air that is being delivered, and is a common metric used for carburetors, pneumatic tools, and air-compressor systems.
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 and of pressure.