Convert Pound square feet to Pound square inches

Convert Pound square feet (lb·ft²) to Pound square inches (lb·in²) instantly and accurately.

Pound square feet (lb·ft²)
Pound square inches (lb·in²)

Conversion Formula

lb·in² = lb·ft² × 144

About Pound square feet

The pound square foot (lb·ft²) equals ≈0.04214 kg·m², the dominant imperial unit for machine and vehicle rotational inertias. Aircraft control-surface counterbalancing, propeller blade inertia, and turbocharger rotor dynamics are specified in lb·ft²; steam turbine discs and helicopter tail-rotor assemblies: 1-10 000 lb·ft². 1 lb·ft² ≈0.04214 kg·m² = 144 lb·in² ≈0.03108 slug·ft².

About Pound square inches

The pound square inch (lb·in²) equals ≈2.926 × 10⁻⁴ kg·m², the standard US customary unit for motor and machinery rotors. Rockwell Automation, Parker Hannifin, and Allied Motion servo sizing catalogs express rotor inertia in lb·in²; US machine-tool spindle and conveyor drive specifications use lb·in². High-speed spindle rotors: 5-50 lb·in². 1 lb·in² ≈2.926 × 10⁻⁴ kg·m² = 1/144 lb·ft².

Quick Reference Table

Pound square feet (lb·ft²)Pound square inches (lb·in²)
1 lb·ft²144 lb·in²
2 lb·ft²288 lb·in²
5 lb·ft²720 lb·in²
10 lb·ft²1440 lb·in²
25 lb·ft²3600 lb·in²
50 lb·ft²7200 lb·in²
100 lb·ft²14400 lb·in²

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