Density = mass ÷ volume
Density tells you how much mass is packed into a volume. Choose what to solve for, enter the other two values with their units (grams, kilograms or pounds; cm³, litres, m³ or cubic feet), and get the answer in g/cm³, kg/m³ or lb/ft³.
The result is compared with water (1 g/cm³): denser materials sink, lighter ones float — a quick sanity check for experiments.
How to calculate density
- 1
Choose what to solve for
Density, mass or volume.
- 2
Enter the known values
With their units.
- 3
Read the result
And compare with water.
Key features
Solve any variable
ρ, m or V.
Many units
Metric and imperial.
Water comparison
Floats or sinks.
Instant
Updates as you type.
Common uses
- Science classes: Density experiments and homework.
- Engineering: Material weight from volume.
- Cooking and shipping: Convert volume to weight.
Tips and good to know
- Density changes slightly with temperature, especially for gases and liquids.
- 1 g/cm³ = 1,000 kg/m³ = 1 g/mL.
Frequently asked questions
What is the density formula?
ρ = m ÷ V. A 250 g object with a volume of 100 cm³ has a density of 2.5 g/cm³.
How do I find mass from density?
Choose Mass: mass = density × volume.
What is the density of water?
About 1 g/cm³ (1,000 kg/m³) at 4 °C.