Density is a fundamental physical property defined as mass per unit volume. In engineering and scientific contexts, two of the most common units used to express density are the kilogram per cubic meter (kg/m³) and the gram per cubic centimeter (g/cm³).
Kilogram per cubic meter (kg/m³): This is the SI derived unit for density. It is widely used in large-scale industrial applications, such as calculating the mass of structural steel, concrete, or the density of air in HVAC systems.
Gram per cubic centimeter (g/cm³): This unit is frequently used in laboratory settings, chemistry, and materials science. It is numerically equivalent to grams per milliliter (g/mL).
The relationship between these units is derived from the conversion factors of mass (1 kg = 1000 g) and volume (1 m³ = 1,000,000 cm³). Consequently, the conversion factor is \(1 \text{ kg/m}^3 = 0.001 \text{ g/cm}^3\). This simple decimal shift makes it easy to transition between macro-scale engineering calculations and micro-scale laboratory analysis.
Kilogram per cubic meter to Gram per cubic centimeter Conversion Reference Table
Kilogram per cubic meter (kg/m³)
Gram per cubic centimeter (g/cm³)
0.1
1.0000e-04
0.5
5.0000e-04
1.0
0.001
2.0
0.002
5.0
0.005
10.0
0.01
20.0
0.02
50.0
0.05
100.0
0.1
500.0
0.5
1000.0
1
Conversion Example: 10 kg/m³ to g/cm³
To convert a density value from kg/m³ to g/cm³, multiply the value by 0.001. Follow these steps:
Identify the initial value: 10 kg/m³.
Apply the conversion factor: \(10 \times 0.001 = 0.01\).
Since 1 gram is 0.001 kilograms and 1 cubic centimeter is 0.000001 cubic meters, the ratio of 1 g/cm³ results in 1000 kg/m³. This is the density of liquid water at standard temperature and pressure.
Use kg/m³ for large-scale structural or fluid mechanics projects to align with SI standards. Use g/cm³ when working with small material samples or chemical concentrations in a laboratory environment.
"On fait la science avec des faits, comme on fait une maison avec des pierres ; mais une accumulation de faits n'est pas plus une science qu'un tas de pierres n'est une maison." "Science is built up of facts, as a house is built of stones; but an accumulation of facts is no more a science than a heap of stones is a house." — Henri Poincaré (French Mathematician, Theoretical Physicist & Mining Engineer)