The density calculator solves ρ = m/V for any of three variables: density, mass, or volume. Supports kg/m³, g/cm³, and lb/ft³. Essential for materials science, chemistry, and fluid dynamics calculations.
Density Calculator (ρ = m/V)
How to Use the Density Calculator
The density formula ρ = m/V relates three properties. This calculator solves for any one given the other two.
Select Units
Choose SI (kg/m³), CGS (g/cm³, most common for chemistry), or Imperial (lb/ft³). Water's density is 1000 kg/m³ = 1 g/cm³ = 62.4 lb/ft³.
Examples
Gold: 19,300 kg/m³ (or 19.3 g/cm³). A 1 cm³ cube of gold has mass = 19.3 g. Air: 1.225 kg/m³ at sea level. A 1 m³ of air weighs 1.225 kg. Ice: 917 kg/m³ — less than water (1000 kg/m³), which is why ice floats.
Float or Sink?
Any material with density less than the surrounding fluid floats. Ice (917 kg/m³) floats in water (1000 kg/m³). Steel (7,800 kg/m³) sinks. Wood (500-800 kg/m³) typically floats.
Frequently Asked Questions
What is the density formula?
Density ρ = m/V, where m is mass and V is volume. Common units: kg/m³ (SI), g/cm³ (CGS), or lb/ft³ (imperial). Water's density is 1,000 kg/m³ = 1 g/cm³ = 62.4 lb/ft³ at 4°C. A material with density > 1 g/cm³ sinks in water; < 1 g/cm³ floats.
What is the density of common materials?
Water: 1.0 g/cm³. Aluminum: 2.7 g/cm³. Steel: ~7.8 g/cm³. Gold: 19.3 g/cm³. Ice: 0.917 g/cm³ (which is why it floats). Air at sea level: 0.00129 g/cm³. Wood varies widely: balsa ~0.12, oak ~0.75 g/cm³.
Is this calculator free?
Yes, completely free with no signup required. All calculations run in your browser.
Is my data private?
Yes. All calculations run locally. Nothing is transmitted.
How do I find the volume of an irregular object?
Use Archimedes' displacement method: submerge the object in water and measure the volume of water displaced. The displaced volume equals the object's volume. Then density = mass / displaced volume.