Density Calculator
Calculate density (ρ), mass, or volume — solve any variable from the other two
Solve For
Mass
Volume
Density (kg/m³)
kg/m³
Common Densities (kg/m³)
Water: 1,000 · Ice: 917 · Air: 1.225
Aluminum: 2,700 · Iron: 7,874
Gold: 19,300 · Wood (oak): ~700
Results
Density (ρ)
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Mass
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Volume
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vs Water
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What is Density?
Density is the mass per unit volume of a substance (ρ = m/V). It's measured in kg/m³ (SI) or g/cm³. An object denser than water (1,000 kg/m³) sinks; less dense objects float. This is Archimedes' principle.
Density is used across science and engineering — from material selection and buoyancy to quality control and identifying unknown substances. For example, pure gold (19,300 kg/m³) is far denser than pyrite (fool's gold, ~5,000 kg/m³), making density a simple purity test.
lightbulb Example
500 g of substance in 250 mL:
1m = 0.5 kg, V = 0.00025 m³
2ρ = m/V = 0.5/0.00025 = 2000 kg/m³
✓ Denser than water — it will sink
quizFrequently Asked Questions
What is the density of common materials?
Water: 1 g/cm³ (1000 kg/m³). Aluminium: 2.7 g/cm³. Steel: 7.8–7.9 g/cm³. Copper: 8.9 g/cm³. Gold: 19.3 g/cm³. Wood (pine): ~0.5 g/cm³. Concrete: ~2.3 g/cm³. Air at sea level: 0.0012 g/cm³. Any material with density less than 1 g/cm³ will float on water.
Why do objects float or sink?
An object floats if its average density is less than the fluid's density. A steel ship floats because its hull traps air — the average density of the ship (steel + air inside) is less than water. A solid steel block sinks because its density (~7.8 g/cm³) is greater than water (1 g/cm³). This is Archimedes' principle.
How is density used in quality control?
Manufacturers use density to verify material purity (pure gold vs. gold-plated metals), detect defects (voids in casting reduce average density), and ensure correct formulations in food, pharmaceuticals, and cosmetics. A density measurement outside the specified range is a red flag for adulteration or manufacturing error.