Quick answer: Mass is density times volume: 1.5 m³ of concrete at 2,400 kg/m³ has a mass of 2,400 × 1.5 = 3,600 kg (3.6 tonnes).
How it's calculated
m = ρ × V, where ρ is density in kg/m³ and V is volume in m³. This is the density formula ρ = m ÷ V rearranged. Volumes in litres, cm³, ft³ or gallons are converted to m³ first (1 L = 0.001 m³).
Mass is the amount of matter and is the same everywhere. Weight is the force gravity puts on that mass; on Earth it is m × 9.80665 m/s², shown in newtons.
The material list uses typical densities. For an exact figure use the value from your supplier's data sheet (ready-mix concrete, steel grade, fuel) with the Other option.
Worked examples
- 1.5 m³ of concrete: 2,400 × 1.5 = 3,600 kg
- 200 L of water (4 °C): 1,000 × 0.2 = 200 kg
- A steel plate 2 m × 1 m × 10 mm (0.02 m³): 7,850 × 0.02 = 157 kg
Mass of one cubic metre
| Material | kg per m³ | kg per litre |
|---|---|---|
| Air (20 °C, sea level) | 1.204 | 0.001204 |
| Petrol (gasoline) | 740 | 0.74 |
| Olive oil | 910 | 0.91 |
| Ice | 917 | 0.917 |
| Water (4 °C) | 1,000 | 1 |
| Seawater | 1,025 | 1.025 |
| Concrete | 2,400 | 2.4 |
| Aluminium | 2,700 | 2.7 |
| Steel | 7,850 | 7.85 |
| Copper | 8,960 | 8.96 |
| Gold | 19,300 | 19.3 |
Frequently asked questions
How do I find mass from density and volume?
Multiply them: m = ρ × V. With ρ in kg/m³ and V in m³ the answer is in kg.
Is mass the same as weight?
No. Mass is measured in kilograms and does not change; weight is a force in newtons that depends on gravity. Everyday scales show mass.
How heavy is a cubic metre of concrete?
About 2,400 kg for normal reinforced concrete; lightweight concrete can be under 2,000 kg.
How heavy is a litre of water?
About a kilogram. At room temperature it's 998 g, close enough.
How heavy is a cubic metre of steel?
About 7,850 kg, more than three times the weight of the same block of concrete.
How heavy is a tank of diesel?
Diesel is around 0.83 to 0.85 kg per litre, so 1,000 litres weighs about 840 kg.