Engineering
Density Calculator
Calculator
Density relates how much mass occupies a given volume (ρ = m / V). This calculator solves for density, mass, or volume given the other two. Useful for material identification, buoyancy problems, weight estimation for shipping, and mixture calculations.
Formula
Formula
ρ = m / V
ρ (rho) is density in kg/m³. m is mass in kg. V is volume in m³. To get g/cm³ divide by 1,000 (since 1 g/cm³ = 1,000 kg/m³). To get lb/ft³ multiply by 0.062428.
Worked example
A steel block has a mass of 7.85 kg and a volume of 0.001 m³ (1 liter). What is its density?
- 1.ρ = m / V = 7.85 kg / 0.001 m³
- 2.ρ = 7,850 kg/m³
- 3.In g/cm³: 7,850 / 1,000 = 7.85 g/cm³ (consistent with mild steel)
- 4.In lb/ft³: 7,850 × 0.062428 = 490.1 lb/ft³
Density = 7,850 kg/m³ = 7.85 g/cm³ — consistent with mild steel.
Assumptions and limitations
- Assumes uniform density throughout the material.
- Mass in kg, volume in m³.
- Does not account for porosity, moisture content, or temperature variation in density.