The Density Formula

Density ρ = mass m ÷ volume V. This density calculator solves for any of the three variables — given mass and volume it finds density; given density and volume it finds mass; given mass and density it finds volume. All conversions use exact factors: 1 g/cm³ = 1,000 kg/m³ = 62.428 lb/ft³.

Common Densities

Water 1.0 · aluminum 2.7 · iron 7.87 · lead 11.34 · gold 19.3 (all g/cm³). Air at sea level is about 0.001225 g/cm³ — 816× less dense than water. Density explains buoyancy, metal identification, and why helium balloons rise.

Applications

Density is used in quality control (detecting diluted fuel or milk), hydrometer design (battery charge, beer gravity), materials selection (lightweight aircraft alloys), and earth science (rock and soil classification). Specific gravity simplifies comparisons since it removes unit conversions entirely.