Mostly it’s true that higher density foams that weigh more are firmer (more unyielding when pressed), but there are exceptions too. Density and weight are now always directly proportional to the firmness of the material. Shortly, the density of the foam means the mass of the foam that is measurable in one specific size. The foam density scale ranges from 24 kg/m3 up to 300 kg/m3. Polyethylene and polyurethane foam density depends on the manufacturing process. This unit of measurement is important: foam density defines what is the use of the material. How to measure foam density? Foam density is measured in kilograms per cubic meter. Home // Foam compass // Foam Density, Weight, Firmness and Usabilityįoam Density, Weight, Firmness and Usability