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Pounds-force to kilograms-force

Multiply pounds-force by 0.453592 to get kilograms-force.

1 lbf = 0.453592 kgfNIST SP 811
lbf
22.6796kgf

50 lbf = 22.6796 kgf

How to convert pounds-force to kilograms-force

The kilogram-force is the force of one kilogram under standard gravity, exactly 9.80665 N. The pound-force is the force of one pound under standard gravity, exactly 4.4482216152605 N.

Worked example — 50 lbf: 50 × 0.453592 = 22.6796 kgf.

Pounds-force to kilograms-force table

Common conversions.
Pounds-forceKilograms-force
1 lbf0.453592 kgf
5 lbf2.268 kgf
10 lbf4.5359 kgf
25 lbf11.3398 kgf
50 lbf22.6796 kgf
100 lbf45.3592 kgf
200 lbf90.7185 kgf
500 lbf226.7962 kgf
1,000 lbf453.5924 kgf

Reverse and related

About pounds-force and kilograms-force

Pound-force (lbf)

1 lbf = 0.453592 kgf

Definition. The force of one pound under standard gravity, exactly 4.4482216152605 N

History and origin

The pound-force is the weight of one pound of mass under standard gravity, a natural force unit in the imperial system. It equals about 4.448 newtons.

Current use

Pounds-force are used in US engineering and to quote thrust, such as a rocket engine rating.

Source: NIST SP 811, App. B (force). lbf and kgf are exact via the pound/kilogram and standard gravity 9.80665 m/s² (CGPM 1901); SP 811 prints them rounded

Kilogram-force (kgf)

1 kgf = 2.2046 lbf

Definition. The force of one kilogram under standard gravity, exactly 9.80665 N

History and origin

The kilogram-force, also called the kilopond, is the weight of one kilogram under standard gravity, exactly 9.80665 newtons. It was common before the newton became standard.

Current use

Kilograms-force still appear in some engineering and in torque specifications outside the United States.

Source: NIST SP 811, App. B (force). lbf and kgf are exact via the pound/kilogram and standard gravity 9.80665 m/s² (CGPM 1901); SP 811 prints them rounded

Where people use this

Pounds-force: US engineering, thrust ratings. Kilograms-force: engineering outside the US, torque specs. 1 lbf is about 0.454 kgf.

How we know this is right
The factor is fixed by the standards that define the units, not chosen — so it is exact, not a measurement:
1 kgf = 2.204622622 lbf, so 1 lbf = 1 ÷ 2.204622622 = 0.453592 kgf.

Every value is carried to full double precision; the display is rounded.

Both units are defined in NIST SP 811, App. B (force). lbf and kgf are exact via the pound/kilogram and standard gravity 9.80665 m/s² (CGPM 1901); SP 811 prints them rounded.

Questions people ask

How many kgf is 1 lbf?

One pound-force is about 0.454 kgf.

How many lbf in a kgf?

One kilogram-force is about 2.205 lbf.

How many kgf is 100 lbf?

100 lbf is about 45.4 kgf.

All pound-force conversions