Mattress firmness is one of the most important but also most confusing things to think about when you buy a new bed. Firmness relates to the immediate feeling you notice when you lie on a mattress; if the surface feels soft or hard against the body. Basically, firmness is how much the mattress pushes back against you.

Firm mattresses resist a lot while soft mattresses almost do not and occasionally simply cave in

Mattress Firmness: What It Means and How to Pick One

Mattress can be firm yet lack real support or give the wrong kind of support. Likewise, soft mattress can be surprisingly supportive. That is important to keep in mind.

Firmness and support are not the same thing.

Although there is no official industry measure for firmness, you commonly use a 10-point scale as a widely accepted standard. Rating 1 is the softest possible, and 10 the most hard. The actual terms that makers use range slightly, some say “plush” instead of “soft”.

Mattresses rated 1 usually have a lot of soft stuffing and a lot of sink. Rating 2 (3 are very soft and very common types), plush with clearly visible sinkage. The range 4 (7 is the most common for mattresses), middle between soft and firm, with a bit of sink and contouring.

Medium soft mattress commonly sits around 4 out of 10, while medium firm could be approximately 6 out of 10. Both are clearly in the centre, but they can appeal to different slepeers.

Although makers design their beds with a specific firmness, it is important to notice that this is subjective. The medium firmness, as declared by the company, does not always match what folks actually feel. A heavier person puts more weight on the mattress, so a firm mattress can feel different for them.

Height and weight matter a lot because they affect the way the mattress reacts. Foam or springs compact according to the amount of pressure applied.

Side sleepers widely do best with softer mattresses. If your current mattress feels as if it pushes the hip or shoulder upward, that is a sign that it is too firm. For side sleepers, medium or medium firm mattress commonly is the best spot.

Stomach sleepers require more support around the neck and the base of the spine, so a firm mattress is best, because it backs the natural curve of the spine and helps avoid neck and back pain. A stomach sleeper lying on a soft mattress can sink in, which pulls the neck or the lower back.

Factors like materials and construction mostly determine how firm a mattress feels. Most models are made up of a comfort system layered above a support core. The comfort system usually is designed to cushion pressure points such as the hips.

Firmer mattresses commonly have denser foam or more high-rate coils to add support. Firm mattress also allows only minimal sinkage, which can help air circulation and better sleep.