Convert Kilograms and liters

kg/m³ means kilograms per cubic meter and is identical to grams per liter. g/cm³ means grams per cubic centimeter and is identical to kilograms per liter.

Example: Iron has a density of 7.874 g/cm³. A cube with an edge length of 20 centimeters has a volume of 8 liters. Made of solid iron, this cube would weigh just under 63 kilograms.

One liter is one cubic decimeter, corresponding to a cube with an edge length of one decimeter or ten centimeters. The kilogram was originally defined so that one liter of water should have this mass. Therefore, it is no coincidence that one liter of water weighs approximately one kilogram. To be precise, however, a liter of water weighs slightly less at normal pressure and any temperature at which it is liquid. Its densest point is at four degrees Celsius, at 0.999975 kilograms per liter.

The density depends on the type of material, as well as on the temperature and pressure. For homogeneous materials, the value can be found in relevant tables; for mixtures of different substances, one often has to rely on empirical calculations, so one must weigh and measure the volume to determine the density. For example, ships are often made of steel, which naturally has a higher density than water. However, they contain a lot of air, which makes the average density of the entire ship less than the density of water, which is why the ship floats.

Physics commonly uses SI units. Here is a calculator to convert units.