Pound per Cubic Inch (lb/in³)
The pound per cubic inch (lb/in³) is used for metal and plastic densities in US engineering, about 27 680 kg/m³.
Symbol: lb/in³ (ASCII: lb/in3)
Quantity: density (mass per unit volume) and mass concentration
SI relation: 1 lb/in³ = 27679.9047102 kg/m³ (exact)
Derivation: 1 lb/in³ = 0.45359237 kg ÷ 1.6387064 × 10⁻⁵ m³ = 27 679.9047 kg/m³
Exact: yes, by definition
Typical uses
- Metal densities (steel ≈ 0.284 lb/in³, aluminium ≈ 0.098 lb/in³)
- CAD material libraries in inch units
- Part weight estimates
Convert pounds per cubic inch to other units
| Conversion | 1 lb/in³ equals | Reverse |
|---|---|---|
| pound per cubic inch to kilogram per cubic meter | 27679.90471 kg/m³ | kilogram per cubic meter to pound per cubic inch |
| pound per cubic inch to gram per cubic centimeter | 27.67990471 g/cm³ | gram per cubic centimeter to pound per cubic inch |
| pound per cubic inch to milligram per liter | 27679904.71 mg/L | milligram per liter to pound per cubic inch |
| pound per cubic inch to pound per cubic foot | 1728 lb/ft³ | pound per cubic foot to pound per cubic inch |
| pound per cubic inch to pound per gallon | 231 lb/gal | pound per gallon to pound per cubic inch |
| pound per cubic inch to kilogram per liter | 27.67990471 kg/L | kilogram per liter to pound per cubic inch |
| pound per cubic inch to gram per liter | 27679.90471 g/L | gram per liter to pound per cubic inch |
Open the Density Converter to convert any value between all units.
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 cubic inch (lb/in³)".
Last reviewed: . Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.
Cite this page
APA
Scientific Converters. (2026, October 15). Pound per Cubic Inch (lb/in³). Retrieved October 17, 2026, from https://scientificconverters.com/units/pound-per-cubic-inch/
IEEE
Scientific Converters, "Pound per Cubic Inch (lb/in³)," scientificconverters.com. Accessed: Oct. 17, 2026. [Online]. Available: https://scientificconverters.com/units/pound-per-cubic-inch/