How a Density Calculator Works
Density measures how much mass is packed into a given volume. This calculator uses the relationship ρ = m/V and lets you solve for any of the three variables by entering the other two. It supports a wide range of units and converts everything to SI internally for accuracy.
Density is one of the most useful properties for identifying materials and predicting whether objects will float or sink. The calculator also lists common material densities so you can quickly compare your result.
The Formula
- Density = Mass ÷ Volume (ρ = m / V)
- Mass = Density × Volume (m = ρ × V)
- Volume = Mass ÷ Density (V = m / ρ)
Density and Buoyancy
Whether something floats depends on how its density compares to the fluid around it.
- Pure water has a density of 1.00 g/cm³, the standard benchmark.
- Objects less dense than water, such as ice (0.92) and most wood (~0.5), float.
- Denser materials like aluminum (2.70), iron (7.87), and gold (19.3) sink.
- Note that 1 g/cm³ equals 1 g/mL equals 1000 kg/m³.
Frequently Asked Questions
What is the density of water?
Pure water has a density of about 1.00 g/cm³ (equivalently 1000 kg/m³ or 1 g/mL) at 4°C. It is the standard reference for comparing other materials and determining whether they float or sink.
How do I know if an object will float?
Compare its density to that of the fluid. An object floats in water if its density is less than 1.00 g/cm³ and sinks if greater. This is why ice and wood float while metals sink.
Are g/cm³ and g/mL the same thing?
Yes. One cubic centimeter equals exactly one milliliter, so a density expressed in g/cm³ is numerically identical to the same value in g/mL. Both also equal 1000 times the value in kg/m³.