# Cubic foot

The cubic foot (symbol ft3 or cu ft)[1] 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 135 of a cubic metre).

cubic foot
Unit systemImperial and US Customary
Unit ofVolume
Symbolft3, cu ft
Conversions
1 ft3 in ...... is equal to ...
US Customary   1728 in3
127 yd3
SI units   0.02831685 m3

## Conversions

 1 cubic foot = 1728 cubic inches = 1⁄27 of a cubic yard ≈ 0.037037 yd3 = 0.028316846592 m3 = 28.316846592 L = 576⁄77 US fluid gallons ≈ 7.4805 US fl gal = 73728⁄77 US fluid ounces ≈ 957.5065 US fl oz ≈ 6.2288 imperial gallons ≈ 996.61 imperial fluid ounces ≈ 0.80356 US bushels ≈ 0.17811 oil barrel

## Symbols and abbreviations

The IEEE symbol for the cubic foot is ft3.[1] The following abbreviations are used: cubic feet, cubic foot, cubic ft, cu feet, cu foot, cu ft, cu.ft, cuft, cb ft, cb.ft, cbft, cbf, feet3, foot3, ft3, feet/-3, foot/-3, ft/-3.[citation needed]

Larger multiples are in common usage in commerce and industry in the United States:

• CCF or HCF: Centum (Latin hundred) cubic feet; i.e., 100 ft3
• MCF: Mille (Latin thousand) cubic feet; i.e., 1000 ft3
• MMCF: Mille mille cubic feet; i.e., 1000000 ft3
• MMCFD: MMCF per day; i.e., 1000000 ft3/d
• BCF or TMC: Billion or thousand million cubic feet; i.e., 1000000000 ft3
• TMC is usually used for referring to storage capacity and actual storage volume of storage dams.
• TCF: Trillion cubic feet; i.e., 1000000000000 ft3
• Used in the oil and gas industry.

## Cubic foot per second and related flow rates

The IEEE symbol for the cubic foot per second is ft3/s.[1] The following other abbreviations are also sometimes used:

• ft3/sec
• cu ft/s
• cfs or CFS
• cusec
• second-feet

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,[2] used mostly in the United States in the context of water flow, particularly of rivers and canals.

Conversions: 1 ft3s−1 = 0.0283168 m3/s = 28.3168 L/s = 1.699011 m3/min = 1,699.011 L/min

### Cubic foot per minute

The IEEE symbol for the cubic foot per minute is ft3/min.[1] The following abbreviations are used:

• cu ft/min
• cufm
• cfm or CFM
• cfpm or CFPM

Cubic feet per minute is used to measure the amount of air that is being delivered, and is a common metric used for carburettors,[3] pneumatic tools, and air-compressor systems.[4]

## Standard cubic foot

A standard cubic foot (abbreviated scf) is a measure of quantity of gas, sometimes[clarification needed] 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.[citation needed]

1. ^ a b c d IEEE Standard Letter Symbols for Units of Measurement (SI Units, Customary Inch-Pound Units, and Certain Other Units) (Revision of IEEE Std 260.1-1993). IEEE Std 260.1-2004 (2004 ed.). Piscataway, N.J.: IEEE. 2004-09-24. pp. 1–30. doi:10.1109/IEEESTD.2004.94618. ISBN 978-1-5044-0928-5. STD95220 STDPD95220 STDPL95220. Archived from the original (PDF or hardcopy) on 2018-06-12. Retrieved 22 December 2019. `{{cite book}}`: `|website=` ignored (help) [1], ISBN 978-0-7381-3997-5, ISBN 978-0-7381-3998-2.