Density from mass and volume — or find mass or volume when you know the other two.
Enter any two of the three values and the third is calculated. Leave one box empty — that is the value to find.
Tap a material to fill its density in. Densities vary with temperature and composition, so these are typical values at around 20 °C.
Density
How to use this tool
Pick whether you want density, mass or volume — simply leave that box empty.
Type the two values you know and choose the right units for each (kg, g or lb for mass; m³, litres, mL, cm³ or ft³ for volume).
The missing value appears instantly, together with the density in every common unit.
Tap a material button to fill in a typical density, then change the mass or volume to see the rest.
Formula & worked example
A block with a mass of 2 kg and a volume of 0.002 m³ has a density of 2 ÷ 0.002 = 1,000 kg/m³ — the density of water. In the other direction, 5 litres (0.005 m³) of a liquid with a density of 850 kg/m³ has a mass of 850 × 0.005 = 4.25 kg.
Limitations — read this before you rely on it
Density alone does not identify a material: different alloys, woods and mixtures can share a density, and density varies with temperature and pressure (especially for gases). Porous or hollow objects need their overall (bulk) volume, not just the solid part, for a meaningful result.
Frequently asked questions
Density = mass ÷ volume. If you know any two of the three, the third follows: mass = density × volume, and volume = mass ÷ density.
Enter any two values and leave the third empty. The calculator works out the missing one, and also shows the density in kg/m³, g/cm³, g/mL and lb/ft³.
Water is 1,000 kg/m³ (1 g/cm³), air at sea level is about 1.225 kg/m³, aluminium about 2,700 kg/m³, steel about 7,850 kg/m³ and gold about 19,300 kg/m³. Use the material buttons for typical values.
Yes: 1 g/cm³ = 1 g/mL = 1,000 kg/m³. To get lb/ft³, multiply kg/m³ by 0.06243 (so water is 62.43 lb/ft³).
Yes, with one catch: density changes with temperature (warm water and warm air are less dense). The values here are typical at around 20 °C, so treat precise laboratory work with a temperature-specific table.