Calculate density from mass and volume, find mass from density and volume, or find volume from density and mass. Covers all three forms of D = M/V with unit conversion.
Density = Mass / Volume (D = M/V). Rearranged: Mass = Density × Volume, and Volume = Mass / Density. This calculator solves all three forms.
Pure water has a density of 1.000 g/cm³ (or 1000 kg/m³) at 4°C. This is the reference point for specific gravity. Objects with density below 1 g/cm³ float in water.
The SI unit is kg/m³. In chemistry, g/cm³ (or g/mL for liquids) is more common. Note that 1 g/cm³ = 1000 kg/m³.
Ice has a density of 0.917 g/cm³, which is less than liquid water (1.000 g/cm³). Water expands when it freezes because its crystal structure is less compact than the liquid phase.
Specific gravity is the ratio of a substance's density to the density of water at 4°C. It is dimensionless. A specific gravity of 2.7 means the substance is 2.7 times denser than water.
An object floats if its average density is less than the fluid it is in. A steel ship floats because its average density (including air-filled interior) is less than water, even though steel itself (7.87 g/cm³) is denser.
Osmium is the densest natural element at 22.59 g/cm³, followed by iridium at 22.56 g/cm³. Gold is 19.32 g/cm³. These are all significantly denser than lead (11.34 g/cm³).