Convert Poundals to Pound of force

A poundal (pdl) is a unit of force in the FPS system. It’s defined as the force needed to accelerate 1 pound-mass (lbm) at 1 foot per second squared (ft/s²).

A pound-force (lbf) is also a unit of force, based on standard gravity. The key link is that 1 lbf equals the weight force on 1 lbm under standard gravity, which is 32.174 ft/s².

Use this direct conversion:

• 1 lbf = 32.174 poundals (pdl)
• 1 pdl = 0.031081 lbf

Convert poundals to pounds of force (lbf)

Multiply poundals by 0.031081:

• lbf = pdl ÷ 32.174
• lbf = pdl × 0.031081

Examples:

• 10 pdl = 10 ÷ 32.174 = 0.3108 lbf
• 100 pdl = 100 ÷ 32.174 = 3.1081 lbf

This conversion works because both units measure force; they just use different definitions of gravity and acceleration.

What is a poundal (pdl)?

A poundal (pdl) is a unit of force in the foot-pound-second (FPS) system. It’s defined as the force needed to speed up a 1-pound mass by 1 foot per second squared. Poundals show up in older physics texts and some engineering notes.

What is a pound-force (lbf)?

Pound-force (lbf) is a unit of force based on weight under standard gravity. 1 lbf is the force that gravity applies to a 1-pound mass at standard Earth gravity. In the US, lbf is common in mechanical work, load ratings, and basic force problems.

What is the conversion from poundals to pound-force?

The standard conversion is:

• 1 pdl = 1/32.174 lbf
• 1 lbf = 32.174 pdl

So poundals are smaller than pound-force. You need many poundals to make 1 lbf.

How do you convert poundals (pdl) to pound-force (lbf)?

Use this formula:

• lbf = pdl ÷ 32.174

Example:

• 100 pdl ÷ 32.174 = 3.108 lbf (rounded)

For quick estimates, some people use 32.2 instead of 32.174.

Why is 32.174 used in the pdl to lbf conversion?

32.174 comes from standard gravity in FPS units. Standard gravity is 32.174 ft/s². Since poundal is tied to ft/s², and pound-force is tied to standard gravity, that value links the two units.

Is a poundal a unit of mass or force?

A poundal is a unit of force, not mass. It’s easy to mix up terms in the FPS system because “pound” can mean mass (lbm) or force (lbf) depending on context.

What’s the difference between lbm, lbf, and pdl?

• lbm (pound-mass) measures mass.
• lbf (pound-force) measures force based on standard gravity.
• pdl (poundal) measures force based on Newton’s second law (mass times acceleration) in FPS units.

In many problems, pdl connects cleanly to F = m·a when mass is in lbm and acceleration is in ft/s².

Can I convert poundals to pounds (lb)?

Not directly. lb often means pound-mass (lbm), which is mass, not force. Poundals convert to pound-force (lbf), which is force. If you’re working with weight, use lbf.

Do poundals to pound-force conversions depend on location?

If you use standard gravity, the conversion stays the same: 1 lbf = 32.174 pdl. Real gravity changes slightly by location, but lbf is defined using standard gravity, so most conversions use 32.174.

How accurate is it to use 32.2 instead of 32.174?

Using 32.2 is fine for rough work. The difference is small:

• 32.174 vs 32.2 changes results by about 0.08%.

For lab work, detailed engineering, or tight tolerances, use 32.174.

What is 1 poundal in pound-force?

• 1 pdl = 0.031081 lbf (rounded)

That means a poundal is about 3.11% of a pound-force.

What is 1 pound-force in poundals?

• 1 lbf = 32.174 pdl

So 1 lbf equals a little over 32 poundals.