How to convert pounds-force to newtons
To convert a measurement in pounds-force to newtons, multiply the value by 4.448222. The conversion factor comes from the relationship between both units and the newton.
For example, to convert 5 lbf to newtons: 5 × 4.448222 = 22.241108 N.
What is a pound-force?
A pound-force is the force exerted by gravity on a mass of one avoirdupois pound under standard gravity, equal to exactly 4.4482216152605 newtons. The pound-force comes from the imperial and US customary systems, where the pound has historically served as both a unit of mass and of force. It remains standard in US engineering practice.
Common uses of pounds-force include: US mechanical and aerospace engineering; Torque and fastener tension specifications; Rocket and jet engine thrust ratings; Load ratings for hardware and fasteners.
What is a newton?
A newton is the SI derived unit of force, defined as the force needed to accelerate a mass of one kilogram at one meter per second squared (1 N = 1 kg·m/s²). Named after Sir Isaac Newton in recognition of his work on classical mechanics, the unit was adopted by the General Conference on Weights and Measures in 1948 and formally added to the SI system in 1960.
Common uses of newtons include: Physics and engineering force calculations; Structural load and tension analysis; Thrust ratings for small motors and actuators; Material testing (tensile and compressive strength).
When you need to convert pounds-force to newtons
US-designed hardware lists ratings in pounds-force, but analysis software and international standards work in newtons. Converting pounds-force to newtons is a routine step when importing a US component into an SI-based calculation.
Pounds-force to newtons worked examples
Here are some common values converted:
1 lbf = 4.448222 N 5 lbf = 22.241108 N 10 lbf = 44.482216 N 50 lbf = 222.411081 N 100 lbf = 444.822162 N
Frequently asked questions
How many newtons are in one pound-force?
One pound-force (lbf) equals 4.448222 newtons (N). Multiply any value in pounds-force by 4.448222 to convert to newtons.
How do I convert pounds-force to newtons?
Multiply the value in pounds-force by 4.448222. For example, 5 lbf × 4.448222 = 22.241108 N.
How do I convert newtons to pounds-force?
Multiply the value in newtons by 0.2248089431, or divide by 4.448222. Use the swap button on the converter above to reverse the direction.
Is the pound-force to newton conversion exact?
Force conversions use standard definitions: 1 kgf = 9.80665 N and 1 lbf = 4.4482216 N exactly.
What is the formula for pounds-force to newtons?
The formula is: N = lbf × 4.448222. This comes from the definition of both units relative to the newton.