Convert Pounds per Foot-second to lbf·s/ft²

Formula

lbf·s/ft² = lb/(ft·s) × 0.03108095017157

or lbf·s/ft² = lb/(ft·s) ÷ 32.17404855643

Derivation from SI units:

• 1 lb/(ft·s) = 0.45359237 kg ÷ (0.3048 m × 1 s) = 1.4881639436 Pa·s
• 1 lbf·s/ft² = 4.4482216152605 N·s ÷ 0.09290304 m² = 47.880258980 Pa·s
• 1 lb/(ft·s) = 1.48816394357 Pa·s ÷ 47.88025898034 Pa·s per lbf·s/ft² = 0.03108095017157 lbf·s/ft²

Both units are defined exactly, so the factor is exact. Pound per Foot-second definition: pound per foot-second; Pound-force Second per Square Foot definition: pound-force second per square foot.

Worked examples

1. A reading of 0.001 lb/(ft·s) converts to 0.00003108095017 lbf·s/ft².
   0.001 lb/(ft·s) × 0.03108095017 = 0.00003108095017 lbf·s/ft²
2. A value of 0.05 lb/(ft·s) is 0.001554047509 lbf·s/ft².
   0.05 lb/(ft·s) × 0.03108095017 = 0.001554047509 lbf·s/ft²

Where it's used

Pounds per Foot-second are used for heat-transfer and chemical-engineering correlations in US units, while pound-force seconds per square foot appear in US fluid-mechanics textbooks and hydraulics. Both measure dynamic (absolute) viscosity, so the conversion is a fixed factor.

Pound per Foot-second to other dynamic viscosity units

Frequently asked questions

Sources

• Guide for the Use of the International System of Units (SI), NIST Special Publication 811, 2008 Edition, National Institute of Standards and Technology , Appendix B.8, "pound per foot second".
• Guide for the Use of the International System of Units (SI), NIST Special Publication 811, 2008 Edition, National Institute of Standards and Technology , Appendix B.8, "pound-force second per square foot".

Last reviewed: 2026-10-15. Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.