How to use it
- Type two of the values into their boxes, for example Mass m 2.7 and Volume V 1 L. Leave the third box, Density ρ, empty.
- Read the Solved value, which here is the density in kg/m³.
- Check the The sample in several units table, which gives the mass, the volume and the density in kilograms, grams, litres and g/cm³.
The formula and the units
The density of a substance is its mass per unit volume. The SI unit is the kilogram per cubic metre (kg/m³), and the density of water is close to 1 g/cm³, which equals 1000 kg/m³.
ρ = m ÷ V
m = ρ × V
V = m ÷ ρ
1 g/cm³ = 1000 kg/m³ = 1 kg/L
1 L = 0.001 m³ = 1000 cm³- Use the same units throughout: kilograms and cubic metres give kg/m³, and grams and cubic centimetres give g/cm³.
- A litre is a cubic decimetre, so a density in kg/L is multiplied by 1000 to give kg/m³: water is 1 kg/L, which is 1000 kg/m³.
Densities of common materials
The table gives typical densities at 0 °C and 100 kPa (273.15 K), the standard conditions used by Wikipedia, unless a note says otherwise. Real samples vary with purity, temperature and the air or pores they contain, so use the table for a comparison, not for an exact figure.
| Material | Density (kg/m³) | Note |
|---|---|---|
| Hydrogen (gas) | 0.0898 | 0 °C, 100 kPa |
| Air | 1.2 | at sea level |
| Cork | 240 | approximate |
| Pine | 373 | |
| Wood | 700 | seasoned, typical |
| Ice | 916.7 | below 0 °C |
| Water (fresh) | 1,000 | maximum, at about 4 °C |
| Water (sea, 3% salt) | 1,030 | |
| Concrete | 2,400 | |
| Glass | 2,500 | |
| Granite | 2,700 | |
| Aluminium | 2,700 | |
| Titanium | 4,540 | |
| Mild steel | 7,850 | |
| Iron | 7,870 | |
| Brass | 8,600 | |
| Copper | 8,940 | |
| Silver | 10,500 | |
| Lead | 11,340 | |
| Mercury | 13,546 | |
| Gold | 19,320 | |
| Platinum | 21,450 | |
| Osmium | 22,570 | the densest natural element |
What the calculator does not cover
- Mixtures and alloys, whose density depends on the proportions and is not simply the average of the components.
- Porous materials and hollow objects: the density of the material is less than that of the whole object, which holds air inside its volume.
- Corrections for temperature and pressure. Enter the density you measured, under the conditions you measured it in.
Worked example: 2.7 kg of aluminium in a 1 litre block
The mass is 2.7 kg and the volume is 1 L, which is 0.001 m³. So ρ = m ÷ V = 2.7 ÷ 0.001 = 2700 kg/m³, which is 2.7 g/cm³.
This is the density of aluminium in the table above, so the block is pure aluminium, or very nearly so.
| Quantity | Value |
|---|---|
| Mass | 2.7 kg (2700 g) |
| Volume | 0.001 m³ (1 L, 1000 cm³) |
| Density | 2700 kg/m³ (2.7 g/cm³) |
Frequently asked questions
What is the density of water?
Fresh water has a density of 1000 kg/m³, or 1 g/cm³, at about 4 °C, the temperature at which it is densest. It is slightly less at other temperatures, and sea water with 3% salt is about 1030 kg/m³.
Why does ice float on water?
Ice has a density of about 916.7 kg/m³, which is less than the 1000 kg/m³ of water, so a block of ice floats with about nine tenths of its volume under the surface.
How do I convert g/cm³ to kg/m³?
Multiply by 1000. A density of 2.7 g/cm³ is 2700 kg/m³, because one cubic centimetre is one millionth of a cubic metre and one gram is one thousandth of a kilogram.
Can I use the calculator for a gas?
Yes, if you enter the density measured at known conditions. A gas density changes strongly with pressure and temperature, so the mass and volume must be for the same conditions. Hydrogen is 0.0898 kg/m³ at 0 °C and 100 kPa.
Why does the calculator accept litres and mL?
Litres and millilitres are common units of volume: 1 L is 0.001 m³ and 1 mL is 1 cm³. The calculator converts them before it divides, so you can type the volume the way it was measured.
What if I leave the mass empty?
The calculator multiplies the density by the volume to give the mass, with the same units. For a density of 2700 kg/m³ and a volume of 0.5 L, the mass is 2700 × 0.0005 = 1.35 kg.
Sources
Figures and text last checked on Tuesday, November 10, 2026.