Density tells you how much mass is packed into a volume. It explains why ice floats, why helium balloons rise and how to identify materials. Water is about 1,000 kg/m³ (1 g/cm³); gold is over 19 times denser.
How to use the Density Calculator
- Find
- Mass m
- Volume V
- Material
- Density ρ
Results update as you type, every field has its own unit menu, and everything is calculated in your browser.
How it works
Choose what to find and enter the other two values. Use the material list to fill in a reference density.
Inputs explained
| Field | What to enter |
|---|---|
| Find | Choose one: Density, Mass, Volume |
| Mass m | Units: kg, g, mg, t, lb, oz |
| Volume V | Units: L, mL, m³, US gal, ft³ |
| Material | Choose one: Water (4 °C), Seawater, Ice, Air (sea level, 15 °C) … |
| Density ρ | Units: kg/m³, g/cm³, g/mL, lb/ft³, lb/in³ |
What each result means
- Density ρ = [Mass m]÷[Volume V]
- Mass m = [r]×[Volume V]
- Volume V = [Mass m]÷[r]
Example values
How the main result changes when Mass m changes and everything else stays at the example values above:
| Mass m (kg) | Density ρ (kg/m³) |
|---|---|
| 1 | 1,000 |
| 1.5 | 1,500 |
| 2 | 2,000 |
| 2.5 | 2,500 |
| 3 | 3,000 |
| 4 | 4,000 |
Formula
ρ = m / V
Worked example
Inputs: Find: Density; Mass m: 2 kg; Volume V: 1 L.
Results: Density ρ = 2,000 kg/m³; Specific gravity (vs. water) = 2.0001.
Key terms
- Density
- Mass per unit volume.
Frequently asked questions
What is the density of water?
About 1,000 kg/m³ or 1 g/cm³ at 4 °C.
How do I find the density of an irregular object?
Weigh it and measure the water it displaces.
Why does ice float?
It is about 9% less dense than liquid water.
Does density change with temperature?
Yes. Most materials expand and become less dense when heated.