Mattress Firmness Scale: How to Pick Your Level

The mattress firmness scale is a 1-to-10 rating of how soft or hard a mattress feels, where 1 is the softest and 10 is the hardest. Most mattresses sold today land between 3 and 8, and the single most common rating is medium-firm, around a 6 to 6.5. There is no universal "best" number: the right level depends mainly on how you sleep — side, back, stomach, or a mix — and on your body weight, which changes how deeply you sink into the same mattress.

What the firmness scale actually measures

Firmness describes the first impression of a mattress: how much your shoulders and hips sink in when you lie down. It is a comfort judgment, not an engineering spec — the industry has no standardized test behind those numbers, so one brand's 6 can feel like another brand's 7. Treat a firmness rating as a starting filter that narrows the field from dozens of mattresses to a handful, not as a guarantee.

The 1-10 mattress firmness scale, level by level

1-2: Ultra soft

Very deep sinkage with almost no push-back. Almost nobody builds a mattress this soft, because it is hard to keep your spine level on one. You will mostly see this range in toppers.

3-4: Soft / plush

Noticeable cradling around the shoulders and hips, with a slow "hug" if the comfort layer is memory foam. Lighter sleepers and dedicated side sleepers often prefer this range. The trade-off: it can be harder to change positions on, and it may not hold the hips high enough for heavier sleepers.

5-6: Medium

A balanced feel — some contouring at the shoulders and hips, but you stay closer to the surface. This is a common landing spot for couples who sleep in different positions, because it does not commit hard in either direction.

6-7: Medium-firm

The most popular range in mattress retail, and the safest default if you honestly do not know what you want. You feel supported on top of the mattress rather than in it, with just enough give at the shoulders. Most hybrids and many memory foam beds are built to hit somewhere in here.

8: Firm

Minimal sinkage. The surface pushes back quickly, and you sleep clearly on top of the mattress. Stomach sleepers, back sleepers who dislike any cradling, and heavier sleepers who bottom out on softer beds tend to gravitate here.

9-10: Extra firm

Very little give at all. This is a niche but real preference — some people simply sleep better on a hard surface, and some heavier sleepers need this much resistance to keep their hips from dropping. The Plank Firm Luxe from Brooklyn Bedding is a good example of a hybrid built deliberately for this end of the scale.

Which firmness matches your sleep position

Side sleepers

Side sleeping puts your body weight on two narrow points: the shoulder and the hip. A mattress that is too firm leaves those points bearing all the pressure, and one that is too soft lets the hips sink out of line. Most side sleepers do well somewhere in the soft-to-medium range, roughly 4 to 6, where the shoulder can sink in while the waist stays supported.

Back sleepers

Back sleeping needs the lower back supported while the hips stay level with the shoulders. Medium-firm to firm — call it 6 to 8 — is the usual answer. Too soft and the hips settle into a hammock shape; too firm and there is an unsupported gap under the lumbar curve.

Stomach sleepers

Stomach sleeping is the least forgiving position, because the hips are the heaviest point and there is nothing to keep them from sinking first. Firm to extra firm, generally 7 and up, keeps the torso flat. A pillow that is thin or nearly flat helps here too.

Combination sleepers

If you rotate through positions all night, prioritize how easily you can move rather than perfect contouring in any one position. Medium-firm hybrids and latex are popular for this reason — they have enough bounce that you are not fighting your way out of a foam impression each time you turn.

Body weight changes the number

Two people can lie on the same mattress and describe it differently, and neither is wrong. More body weight compresses the comfort layers further, so a mattress rated 6 can feel like a 5 to a heavier sleeper and like a 7 to a lighter one.

A rough working rule: lighter sleepers often want to go one step softer than the position-based recommendation above, and heavier sleepers often want to go one step firmer. Couples with a large weight difference are the classic case for a split king setup, where each side is a separate mattress and each person picks their own firmness.

Firmness and support are not the same thing

This is the distinction that trips up the most shoppers. Firmness is surface feel. Support is whether the mattress keeps your spine in roughly the same alignment it has when you stand up straight.

A plush mattress with a well-built coil or high-density foam core can be perfectly supportive. A cheap firm mattress with a weak core can be unsupportive despite feeling hard. When you are comparing options, look at what is underneath the comfort layer, not just the number on the label.

How material changes the same firmness rating

Two mattresses rated 6 can feel completely different depending on what they are made of:

• Memory foam responds slowly and conforms closely, so it reads as softer than its rating and can feel like it holds you in place. Browse memory foam mattresses if that is the feel you are after.
• Hybrids pair coils with a foam or latex comfort layer, so they push back faster and are easier to move on. Hybrid mattresses are the most common choice in the medium-firm range.
• Latex is buoyant and springy — supportive without the sinking sensation of memory foam.
• Innerspring beds with thin comfort layers usually sit at the firmer end and feel the most traditional.

How to test firmness before you commit

Ten seconds sitting on the edge tells you nothing useful. Lie down in the position you actually sleep in, stay there several minutes with a pillow the height you use at home, then check two things: whether any single point is carrying too much pressure, and whether your lower back feels supported or suspended. Even a careful in-store test is only a preview — your body needs a few weeks to adapt to a new surface, which is why a sleep trial matters more than a showroom impression.

Frequently asked questions

What firmness is best for most people?

Medium-firm, around 6 to 6.5, suits the widest range of sleepers and is the most commonly sold firmness. If you are buying without being able to test first, it is the lowest-risk starting point.

Do mattresses get softer over time?

Slightly. Comfort layers break in over the first several weeks and a new mattress often feels firmer than it will settle at. That break-in is normal and is different from sagging, which is a durability problem rather than a firmness change.

Can I make a mattress softer or firmer?

You can soften a mattress meaningfully with a topper. Firming one up is harder — a firm topper helps a little, but if the core is too soft, a topper will not fix it. Also check that your foundation is solid, since a sagging base can make a good mattress feel wrong.

Should partners with different preferences compromise on one firmness?

Not necessarily. A split king — two Twin XL mattresses side by side — lets each person pick their own firmness on one king-size frame. If you would rather keep a single mattress, a medium-firm with a topper on one side is the usual middle ground.

Is a firmer mattress better for your back?

Not automatically. What matters is spinal alignment, and that depends on your sleep position and body weight as much as on firmness. The old advice to always buy the hardest mattress available is not supported by how mattresses are built today. If you have a specific back concern, talk to your doctor about it.

Try the firmness levels for yourself in Glendale

Numbers only get you so far — firmness is something you have to feel. Our Glendale showroom has soft, medium-firm, firm, and extra-firm models set up side by side, so you can compare the whole mattress range in one visit and see how much a single step on the scale actually changes things. Every mattress comes with a 120-night sleep trial, so you have time to be sure at home, and we offer free delivery and setup across Los Angeles. Come by, tell us how you sleep, and we will narrow it down with you.