Convert Poundal to Pound-Force
Convert Poundal (pdl) to Pound-Force (lbf) instantly and accurately.
Conversion Formula
lbf = pdl × 0.03108095017
About Poundal
The poundal (pdl) is the force unit of the foot-pound-second absolute system - the force to accelerate 1 pound at 1 ft/s² - approximately 0.1383 N. Introduced in 1877 by Thomson and Tait as the FPS analogue of the CGS dyne (1 dyn = 1 g·cm/s²; 1 pdl = 1 lb·ft/s²). The poundal is distinct from pound-force: since standard gravity = 32.174 ft/s², 1 lbf = 32.174 pdl. It survives in older British engineering texts and early 20th-century thermodynamics literature, but is otherwise obsolete. 1 pdl = 0.138254954376 N = 1/32.174 lbf.
About Pound-Force
The pound-force (lbf) is the gravitational force on 1 lb-mass under standard gravity - exactly 4.4482216152605 N. It dominates US structural, mechanical, and aerospace engineering: AISC and ACI structural codes use lbf and kips (1 kip = 1,000 lbf); tire pressure 'psi' means lbf/in²; engine torque in lb·ft. Aircraft thrust is quoted in lbf: the GE90-115B (Boeing 777) produces 115,300 lbf = 513 kN. Spring rates, fastener torques, and load cell calibrations across North America are in lbf. 1 lbf = 4.44822 N = 16 ozf = 32.174 pdl.
Quick Reference Table
| Poundal (pdl) | Pound-Force (lbf) |
|---|---|
| 1 pdl | 0.031081 lbf |
| 2 pdl | 0.0621619 lbf |
| 5 pdl | 0.155405 lbf |
| 10 pdl | 0.31081 lbf |
| 25 pdl | 0.777024 lbf |
| 50 pdl | 1.55405 lbf |
| 100 pdl | 3.1081 lbf |