# Pound-force

The **pound-force** (symbol: **lbf** ^{[note 1]} ) is a measurement unit of force which will accelerate 1 pound of mass to 9.80665 m/s^{2} (≈ 32.17405 ft/s^{2}), the standard average acceleration due to gravity on Earth's surface (referred to as **g _{n}**

^{[1]}). It is used primarily in the United States of America and is equivalent to exactly 4.4482216152605 newtons.

^{[2]}

In common usage and other contexts, it is most often referred to in the United States as a * pound* or as

*, but this can lead to confusion with the pound-mass.*

**lb**## Definition in terms of the SI unit of force

The newton (symbol: N) is the unit of force named in the International System of Units (SI). Using the standard average acceleration due to gravity, denoted * g_{n}*, as being 9.80665 m/s

^{2}and the internationally agreed upon definition of the pound-mass, denoted as

*, as being 0.45359237 kg,*

**lbm**^{[1]}

^{[3]}we can determine the number of newtons exactly equivalent to a pound-force:

## Equivalent units of force

- 1 lbf ≈ 4.448221 newton (symbol:
**N**) - 1 lbf ≈ 4448822 dyne (symbol:
**dyn**) - 1 lbf ≈ 0.453592 kilogram-force (symbol:
**kgf**) - 1 lbf ≈ 0.453592 kilopond (symbol:
**kp**)^{[note 2]} - 1 lbf ≈ 4.448221×10
^{−3}sthène (symbol:**sn**) - 1 lbf ≈ 32.17405 poundal (symbol:
**pdl**) - 1 lbf ≡ 0.001 kip (symbol:
**kip**)^{[note 3]}

## Notes

## References

- ↑
^{1.0}^{1.1}Resolution of the 3rd meeting of the CGPM (1901) Definition of the standard average acceleration due to gravity - ↑ Metric Conversion Table Scroll down to "Force"
- ↑ Appendix 8, Customary System of Weights and Measures U.S. Dept. of Commerce, July 15, 1968. Definition of the pound-mass.