Cubic foot per second

A cubic foot per second (also cfs, cu ft/s, cusec and ft³/s) is an Imperial unit / U.S. customary unit volumetric flow rate, which is equivalent to a volume of 1 cubic foot flowing every second. Current official usage is largely confined to the United States and Canada, but like many imperial units which have officially been "abolished" in the United Kingdom, it remains familiar in that country, with extensive unofficial usage. It is popularly used for pipeline transport rates, water flow in rivers, and for HVAC measurements of air flow.

Symbols

There is no universally agreed symbol but the following are used:

• cu ft/s
• cfs
• ft^3/sec
• ft³/sec
• cusec

Conversions

1 cubic foot per second is the same as:

• 1,728 cubic inches per second
• 7.48051945 US gallons per second
• 6.22883272 Imperial gallons per second
• 28.3293425 litres per second
• 0.0283293425 cubic metres per second
• 31,536,000 cubic feet per year
• 0.000214242111 cubic miles per year
• 723.966942 acre feet per year

See also

• 1 E-1 m³ for a comparison with other volumes
• Cubic mile
• Orders of magnitude (volume)
• Conversion of units