Foam density
1.81" Cooling Gel Memory Foam. 3.1 lb/ft³.
Foam thickness and foam density tell you different things. Thickness tells you how much vertical space a foam layer occupies. Density tells you how much material is contained within a given volume of foam.
Two mattresses can both advertise a similar memory foam layer while using very different foam constructions.
We don’t think “premium foam” tells you enough. So we publish the numbers.
Density is not firmness. A 3.1 lb/ft³ foam is not automatically firmer or more comfortable — it describes how much material is in the layer.