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Science & Engineering

Density Calculator - Mass, Volume & Density Solver

Calculate density, mass, or volume using D = m/V. Supports metric and imperial units with common material density reference.

Leave one field blank - it will be calculated using D = m / V.

Common material densities
Water (4°C)1000 kg/m³
Sea water1025 kg/m³
Air (20°C)1.204 kg/m³
Aluminium2700 kg/m³
Steel7850 kg/m³
Iron7874 kg/m³
Copper8960 kg/m³
Gold19300 kg/m³
Oak wood720 kg/m³
Concrete2300 kg/m³
Ice917 kg/m³
Ethanol789 kg/m³

Density formula

D = m / V — density equals mass divided by volume. Rearranged: m = D × V to find mass, or V = m / D to find volume. The SI unit of density is kg/m³, though g/cm³ is common in chemistry since it gives convenient numbers for everyday materials (water is almost exactly 1 g/cm³).

Common density conversions

  • 1 g/cm³ = 1 g/mL = 1 kg/L = 1000 kg/m³
  • 1 lb/ft³ ≈ 16.018 kg/m³

Material density reference

MaterialDensity (kg/m³)Notes
Air (20°C)1.2Changes significantly with altitude and temperature
Wood (pine)~500Floats in water; varies by species and moisture
Water (4°C)1000Reference point for buoyancy calculations
Ice917Less dense than liquid water — why ice floats
Concrete~2300Varies with aggregate and mix ratio
Aluminum2700Lightest common structural metal
Steel7850Standard structural and engineering material
Lead11340Used in radiation shielding and ballast
Gold19300Nearly 20× denser than water

Archimedes' principle and buoyancy

Archimedes' principle states that an object submerged in a fluid experiences an upward buoyant force equal to the weight of the fluid it displaces. An object floats when that buoyant force equals or exceeds its own weight — which happens when the object's average density is less than or equal to the fluid's density. This is why a solid steel ball sinks (density 7850 kg/m³, far above water's 1000 kg/m³) but a steel ship floats: the hull encloses a large volume of air, bringing the ship's average density below that of water. Ice floats on water for the same reason — it is about 8% less dense than liquid water, which is why roughly 90% of an iceberg sits below the surface.

Density in everyday life

Oil floats on water because most cooking oils have a density around 900 kg/m³, slightly below water. The egg freshness test works because a fresh egg is dense (the air cell inside is tiny), while an older egg has a larger air cell as moisture escapes through the shell, lowering its average density until it floats. In geology, rock samples are weighed in air and then in water to calculate density from the buoyancy difference — a technique that can identify mineral composition without cutting or crushing the sample.