Convert Pound square inches to Slug square inches

Convert Pound square inches (lb·in²) to Slug square inches (slug·in²) instantly and accurately.

Pound square inches (lb·in²)
Slug square inches (slug·in²)

Conversion Formula

slug·in² = lb·in² × 0.03108095017

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.

About Slug square inches

The slug square inch (slug·in²) equals ≈9.415 × 10⁻³ kg·m², used in US aerospace guidance and flight mechanics. Pre-metric inertial navigation unit (INU) test reports and NACA stability-derivative tables listed gyroscope platform inertia in slug·in²; US autopilot servo actuator sizing also uses slug·in². 1 slug·in² ≈9.415 × 10⁻³ kg·m² ≈32.17 lb·in².

Quick Reference Table

Pound square inches (lb·in²)Slug square inches (slug·in²)
1 lb·in²0.031081 slug·in²
2 lb·in²0.0621619 slug·in²
5 lb·in²0.155405 slug·in²
10 lb·in²0.31081 slug·in²
25 lb·in²0.777024 slug·in²
50 lb·in²1.55405 slug·in²
100 lb·in²3.1081 slug·in²

→ Full Moment of Inertia Converter