Moment of Inertia Converter
Convert moment of inertia between kg m², lb ft², g cm², slug ft², and oz in² instantly.
Type in any field — the others update instantly.
Moment of inertia measures how much an object resists rotational acceleration. It depends on both the mass and how far that mass is from the axis of rotation.
All conversions use kg·m² as the base unit.
Metric units:
- 1 kg·m² = 10,000 g·cm² = 10,000,000 g·mm²
- 1 g·cm² = 0.0001 kg·m²
Imperial units:
- 1 lb·ft² = 0.042140 kg·m²
- 1 lb·in² = 0.00029264 kg·m²
- 1 slug·ft² = 1.35582 kg·m²
- 1 oz·in² = 0.000018290 kg·m²
Cross-system:
- 1 kg·m² = 23.7304 lb·ft²
- 1 kg·m² = 0.73756 slug·ft²
Common examples:
- Bicycle wheel: ~0.1 kg·m²
- Car wheel + tire: ~0.5–1.0 kg·m²
- Flywheel (industrial): 10–1000 kg·m²