Density Calculator

Density is the mass per unit volume and is a characteristic property of a substance. At the same volume, a higher density means greater weight.

Enter the mass (g) and volume (cm³) to instantly get the density (g/cm³). Often used in science experiments for identifying substances or calculating buoyancy.

For example, an object with a mass of 1,000 g and a volume of 1,000 cm³ has a density of 1 g/cm³, the same as water.

Density Calculator Calculation Method

ρ: density (g/cm³), m: mass (g), V: volume (cm³)

The density (g/cm³) is 0 .

About This Calculator

Density is how much mass is packed into a given volume, usually expressed in kg/m³ or g/cm³. It explains why some objects float: anything less dense than the surrounding fluid rises, and anything denser sinks.

Enter the mass and volume to find the density, or enter density and one of the other values to solve for the missing quantity.

Density is mass divided by volume, so one litre of water at 4 °C has a mass of 1 kg and a density of 1,000 kg/m³. A 2 kg block occupying 0.0025 m³ therefore has a density of 800 kg/m³ and floats. Air at sea level is about 1.225 kg/m³, roughly eight hundred times lighter than water.

Key Formula:ρ = m / V

Frequently Asked Questions

Why does ice float on water?

Water is unusual in that its solid form is less dense than its liquid form — ice is about 0.92 g/cm³ against 1.00 g/cm³ for liquid water at 4 °C. That is why ice floats and why lakes freeze from the top down.

Is density the same as specific gravity?

Specific gravity is density divided by the density of water, so it is a dimensionless number. A substance with a specific gravity of 1.5 has a density of 1,500 kg/m³.

Why does an object float?

It floats when its average density is lower than the fluid, because the displaced fluid then weighs more than the object. Steel sinks, but a steel ship floats because its hollow hull brings the average density below that of water.

How does temperature change density?

Most substances expand when heated, so the same mass occupies more volume and density falls. Water is unusual in being densest at 4 °C, which is why ice floats and lakes freeze from the surface down.

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Sources & last update

2026-10-19