A density and mass volume calculator solves the density equation ρ = m/V for any unknown. Enter any two of density, mass, and volume to find the third.
Density (ρ) = Mass (m) ÷ Volume (V). This fundamental formula relates three physical properties of any substance. Given any two, you can calculate the third:
Density is measured in kg/m³, g/cm³, or lb/ft³. Water has a density of 1 g/cm³ = 1,000 kg/m³ = 62.43 lb/ft³.
V = m / ρ
Example: What volume does 500 grams of gold occupy?
Gold density = 19.3 g/cm³. V = 500 ÷ 19.3 = 25.91 cm³ = 25.91 mL = 0.026 L.
Example: What volume does 1 kg of water occupy? V = 1,000 g ÷ 1 g/cm³ = 1,000 cm³ = 1 liter.
ρ = 19.3 g/cm³. V = 1,000/19.3 = 51.81 cm³ — surprisingly small!
ρ = 2.7 g/cm³. V = 5,000/2.7 = 1,851.85 cm³ = 1.85 L.
V = 3,785 mL. m = 3,785 × 1 = 3,785 g = 3.785 kg = 8.34 lbs.
ρ ≈ 2,400 kg/m³. V = 0.7646 m³. m = 0.7646 × 2,400 = 1,835 kg ≈ 4,046 lbs.
35 free volume calculation tools — click any calculator to get started.
Answers to common questions about the density & mass volume calculator.
V = mass ÷ density. You must know the material's density. Look up density tables or measure it. Units must be consistent (g and g/cm³, or kg and kg/m³).
Water: 1 g/cm³ = 1,000 kg/m³ = 62.43 lb/ft³ = 8.345 lb/gal (at 4°C). At room temperature (20°C), density is 0.998 g/cm³ — practically unchanged.
Measure mass with a scale. Measure volume by (a) geometric formula for regular shapes, (b) water displacement for irregular objects, or (c) using a graduated container for liquids. ρ = m/V.
Air: 1.225 kg/m³. Water: 1,000 kg/m³. Milk: 1,030 kg/m³. Concrete: 2,400 kg/m³. Steel: 7,850 kg/m³. Gold: 19,300 kg/m³. Aluminum: 2,700 kg/m³. Wood (oak): 600-900 kg/m³.
Yes. Most materials expand when heated (lower density) and contract when cooled (higher density). Water is unusual — it is densest at 4°C, less dense as ice (0°C). This is why ice floats.