How Is Foam Density Measured?

Foam Density

Low

Medium

High

Durability

Poor Low-density foam is more susceptible to sagging and early wear-and-tear, giving mattresses with this material a shorter-than-average lifespan

Fair to Good Medium-density foams are more durable than low-density foams, but some sagging and early wear-and-tear may still occur

Good to Very Good High-density foam has strong longevity; beds made with this material typically have longer-than-average lifespans

Conforming ability

Poor to Fair Low-density foams do not respond to the sleeper’s body temperature as much as higher-density foams, resulting in a minimal amount of body conforming

Good to Very Good Medium-density foams conform fairly consistently, though they don’t provide the same close body hug as high-density foams

Very Good High-density foam conforms closely and consistently to the sleeper’s body, due in part to its high responsiveness to body heat

Pain/pressure relief

Fair to Good Because low density foams tend to conform very little, sleepers may not experience as much pain and pressure relief; that being said, most foam mattresses alleviate discomfort to at least a noticeable extent

Good Most mattresses with medium-density foams – especially memory foam – provide decent pain and pressure relief for sleepers

Very Good High-density foams earn strong ratings for pain and pressure relief due in part to their close conforming ability

Temperature neutrality

Good Low-density foams do not absorb and trap as much body heat, allowing them to sleep cooler than denser foams – but temperature neutrality is still average at best

Fair to Good Medium-density foams trap a fair amount of body heat from sleepers, and will likely be too warm for some people

Poor to Fair High-density foams can be major heat traps, and are not recommended for those who tend to sleep warm or hot

Sex

Fair to Good Foams are generally considered worse for sex than other mattress materials because of their low responsiveness, but low-density foams are springier and may be suitable for some couples

Poor to Fair Medium-density foams are not very responsive; as a result, some couples claim that having sex on these materials results in a sinking feeling they liken to fighting with the mattress

Poor High-density foams are temperature-sensitive and often sink excessively; as a result, many couples complain beds with these foams are not good for sex

Motion isolation

Good Motion isolation is a strength of all foams, but low-density foams tend to minimize the lowest amounts of transfer

Very Good Most medium-density foams absorb and minimize a significant amount of motion transfer

Very Good Like their medium-density counterparts, high-density foams offer strong motion isolation

Noise potential

Excellent With rare exception, mattresses with low-density foam are virtually silent when bearing weight

Excellent Medium-density foam does not make any noise when bearing weight

Excellent Noise potential is an area where all foams excel regardless of density; high-density foams are virtually noise-free as well

Odor potential

Fair Most mattresses with foam components produce off-gassing odor when new, but those with low-density foams tend to produce the lightest and least persistent smells

Fair to Poor The denser the foam, the higher the odor potential; most medium-density foams emit stronger and longer-lasting smells than low-density foams

Poor The strongest and most persistent off-gassing odors are associated with mattresses containing high-density foam layers in the comfort system and support core

Mattress weight

Low Mattresses with low-density foam tend to be lightest; the average weight is about 50 to 65 pounds

Moderate Medium-density foam can drive up the weight by a noticeable degree; the average mattress weight is about 60 to 75 pounds

High High-density foam is naturally the heaviest; beds with high-density foam comfort layers and support cores typically weigh 75 to 90 pounds, or more in some cases

Average price

Low Because low-density foam is relatively inexpensive, mattresses with this material have the lowest average price-point: about $500 to $750

Moderate Mattresses with medium-density foams have middle-of-the-road price-points: about $700 to $950 on average

High Expect higher-than-average prices for mattresses with high-density foam layers outside the support core: about $1,000 to $1,400