The SI unit for density is kilogram per cubic meter (kg/m3).
Density is defined as mass per unit volume. In the International System of Units (SI), mass is measured in kilograms (kg) and volume is measured in cubic meters (m3). Therefore, the ratio of these two quantities, which is density, has the SI unit of kg/m3.
While grams per cubic centimeter (g/cm3) is a commonly used unit, especially because the density of water is approximately 1 g/cm3, it is not the SI unit. To convert from g/cm3 to kg/m3, you would multiply by 1000.