# Kilogram-force

A **kilogram-force** (**kgf**) is a unit of force that will accelerate 1 kilogram of mass at 9.80665 m/s^{2}, the standard acceleration due to gravity on Earth's surface (referred to as * g_{n}*).

^{[1]}The kilogram-force is often referred to as the

*.*

**kilopond (kp)**^{[note 1]}

Since a newton is defined^{[2]}^{[3]} as the force that will accelerate 1 kilogram of mass at 1 m/s^{2}, and acceleration is proportional to force, one kilogram-force is therefore equal to 9.80665 newtons.^{[4]} It is also equal to 2.20462 pounds-force.

The kilogram-force was not very well defined until the 3rd General Conference on Weights and Measures (Conférence Générale des Poids et Mesures, CGPM) defined * g_{n}*, the standard gravity, to be 9.80665 m/s

^{2}in 1901.

^{[5]}Although it was once widely used, it has never been part of the International System of Units (SI) introduced in 1960 by the 11th GCPM.

^{[6]}

The kilogram-force is still used to some extent in a few countries, but it is generally considered to be obsolete in most countries.

## Equivalent units of force

- 1 kgf ≡ 9.80665 newton (symbol:
**N**) - 1 kgf ≡ 980,665 dyne (symbol:
**dyn**) - 1 kgf ≡ 1 kilopond (symbol:
**kp**)^{[note 1]} - 1 kgf ≡ 9.80665×10
^{-3}sthène (symbol:**sn**) - 1 kgf ≈ 2.20462 pound-force (symbol:
**lbf**) - 1 kgf ≈ 2.20462×10
^{-3}kip (symbol:**kip**)^{[note 2]} - 1 kgf ≈ 70.93164 poundal (symbol:
**pdl**)

## Notes

- ↑
^{1.0}^{1.1}Another name for a kilogram-force. Not to be confused with "kilopounds", meaning 1,000 pounds of mass. - ↑ A non-SI unit of force equal to 1,000 pound-force.

## References

- ↑ The International System of Units (SI), NIST Special Publication 330, 2008 Edition (pdf page 57 of 77 pdf pages)
- ↑ Glossary From the website of NASA's Goddard Space Flight Center.
- ↑ The International System of Units (SI), NIST Special Publication 330, 2008 Edition (pdf page 30 of 77 pdf pages)
- ↑ Metric Conversion Table Scroll down to "Force"
- ↑ Resolution of the 3rd meeting of the CGPM (1901)
- ↑ Resolution 12 of the 11th meeting of the CGPM (1960)