When looking for a memory foam mattress, one of the most important aspects to consider is density. Memory foam density is expressed in pounds per cubic foot and is helpful in determining the firmness level of a memory foam mattress. This measurement makes a big difference in the softness, support, durability, and price of your mattress. Another way to think of density is the weight of 1 cubic foot of memory foam, meaning foam that is denser will also weigh more. It's important to note that memory foam density and thickness are two separate and distinct qualities. Remember that density relates to firmness while thickness is the actual height of the mattress.
Memory Foam Mattress Densities:
Low-Density Memory Foam
Low-density memory foam has a measurement of 3 pounds per cubic foot or lower. This kind of memory foam mattress feels softer, and you’ll sink into it more quickly. Most memory foam mattress makers use higher densities because they're more durable and provide more support than low-density foam. However, less dense means less foam, which translates to a more affordable mattress. If you're shopping on a tight budget or like to really sink into your bed, then a low-density memory foam mattress has what you're looking for.
Medium-Density Memory Foam
Memory foam with a density of 4 to 5 pounds per cubic foot is referred to as medium-density foam. Mattresses made with medium-density foam are typically a good blend of comfort, durability, and support with a reasonable price tag. While they're not as soft as low-density memory foam, you'll still sink into comfort without much resistance. These mattresses don't quite offer the level of support a high-density product would, but they should still be enough for the average sleeper. If you're new to memory foam or just aren't really sure what you’re looking for, a medium-density memory foam mattress is a good place to start.
High-Density Memory Foam
Anything 6 pounds per cubic foot or higher is considered high-density memory foam. These mattresses have outstanding support and durability, so you can plan on them lasting a long time. If you're looking for a mattress to relieve back pain, high-density memory foam provides unique support that can lessen body pain and improve circulation. High-density foam may feel stiff at first, but it soon molds to your body and relieves pressure points.
Today, memory foam mattresses don't typically come as one big piece of solid foam but rather as a composite made up of multiple layers of memory foam of varying densities. Mattresses are usually constructed with a thick, high-density base followed by less dense layers of memory foam, gel memory foam, and sometimes even latex foam. These combinations still have different levels of overall density, but having that high-density base gives memory foam mattresses greater longevity and an all-around better construction.