Mattress firmness scale: what the numbers and levels really tell you
The mattress firmness scale runs from 1, the softest, to 10, the firmest, grouped into levels from extra soft to extra firm. Casper, for example, puts medium firm at 5 to 6 and firm at 7 to 8.
There is no standard behind it. Each maker picks its own numbers, so a 7 from one brand is not a measured match for a 7 from another. PlushBeds puts its Med-Firm at 7, 8 or 8.5.
We checked how loose it gets inside one brand. PlushBeds calls a 5, a 5.5 and a 7 "Medium" on different pages, and a 7 is Medium on one of its beds and Med-Firm on another.
Use a number to rank one maker's models. To compare brands, compare what the layers are made of.
The firmness levels and their usual numbers
Makers group the scale into named levels. The names are fairly settled; the numbers attached to them are not. Below, one maker's published ranges next to another maker's actual ratings.
| Level | Casper's range | PlushBeds' ratings |
|---|---|---|
| Extra soft | 1 to 2 | None found |
| Soft | 3 to 4 | None found on a stated 1 to 10 scale |
| Medium | No level of its own in the list | 5, 5.5 or 7 |
| Medium firm | 5 to 6 | 7, 8 or 8.5 |
| Firm | 7 to 8 | None found on a stated 1 to 10 scale |
| Extra firm | 9 to 10 | None found |
Casper's firmness scale article and PlushBeds product pages, read 25 September 2026.
The two makers do not even agree on medium firm. Casper's range stops at 6; every PlushBeds Med-Firm we found is 7 or higher. Neither is wrong. They are two private scales that happen to share a name.
Casper's own article is not consistent either. Its headings run from soft at 1 to firm at 10, while one sentence on the same page says "we generally define firm as from 1-3" and puts soft at 9 to 10.
One brand, one word, three numbers
To see how far a label stretches, we took one maker that prints numbers on every product page and put them side by side. PlushBeds states each figure "out of 10" or on a scale where "1 is the softest bed made and 10 is the hardest".
| PlushBeds page | "Medium" | "Med-Firm" | Scale as stated |
|---|---|---|---|
| Eco Bliss (latex hybrid) | 5 | 7 | "out of 10" |
| Healthy Mattress for Kids (hybrid) | 5 | Not offered | "out of 10" |
| Botanical Bliss (all latex) | 5.5 | 8 | "out of 10" |
| Organic Kids Mattress (all latex) | Not offered | 8 | "out of 10" |
| Natural Bliss (all latex) | 7 | 8.5 | "out of 10" |
Read from each live PlushBeds page on 25 September 2026.
PlushBeds rates its Medium at 5, 5.5 and 7 and its Med-Firm at 7, 8 and 8.5, depending on the page. The two labels meet at 7: Medium on the Natural Bliss, Med-Firm on the Eco Bliss.
Its Heavenly Plush hybrid is left off. It rates its versions 9, 7 and 4.5 but never says what the top of that scale is, so placing it on 1 to 10 would be our guess.
The brand disagrees with itself about what the numbers are. A PlushBeds blog post says there is "no universally accepted measurement of mattress firmness". Its firmness options page, written around the Botanical Bliss, calls the same thing "the standard firmness scale" and says the numbers let you compare against any bed you have slept on.
That page also says every PlushBeds bedroom mattress comes in the same two firmness options, 5.5 and 8. The Eco Bliss and Natural Bliss product pages, above, print 5 and 7, and 7 and 8.5.
Our reading: the blog post is the accurate one. Casper, another maker, says the same on its own blog, and the table above shows the numbers do not line up even inside one company.
Not stated: whether PlushBeds rates every model on one shared scale, or each line on its own. None of the pages says. If the scale is shared, a Natural Bliss Medium is firmer than an Eco Bliss Medium. If it is not, the two numbers cannot be compared at all.
This is not a flaw peculiar to one maker. It is simply what a scale with no standard looks like once you line the numbers up. Our guide to plush vs firm mattresses shows the same thing from the other side, in the layers of one bed sold in three firmnesses.
ILD: the layer number behind the feel
Latex and foam layers often carry a second number, ILD, short for indentation load deflection. It is a lab figure for how much force it takes to press the material down. Higher means firmer.
ILD is closer to a measurement than a 1 to 10 rating, but it describes one layer, not the whole bed. A soft top over firm latex can feel medium while no single layer is medium.
It is not always printed consistently either. The PlushBeds organic latex topper page lists five firmness options from 14 ILD for Soft to 44 ILD for Extra Firm, and a second table on the same page gives Extra Firm as 40 to 42 ILD. Some latex is rated on a D scale instead: the brand's kids beds list D65 for the Medium hybrid and D85 for the Med-Firm all-latex model.
For toppers, where one layer is the whole product, ILD is the more useful figure. Our guide to the firm mattress topper covers that side.
How to use a firmness number when you shop
- Compare numbers only within one brand. A maker's 5 is softer than the same maker's 7. Across brands, the gap is unknown.
- Read the number next to the word. "Medium 5" and "Medium 7" are different beds, even from one seller.
- Check what the top of the scale is. If a page gives a number without saying out of what, you cannot place it.
- Compare construction across brands. Look at what sits above the support and what it is made of. Our guide to types of mattresses explains the main builds, and medium vs firm mattresses shows how the layers change inside one bed.
- Read the trial and exchange terms. A number is a promise about feel, not a measurement of it, so what happens if it feels wrong matters.
What we are not telling you
Many firmness scale pages match numbers to sleeping positions, body weights or back pain. We are not doing that. The figures we found for those were unsourced, and firmness for a medical need is not something we can check.
We have not slept on these beds or tested their layers. Everything above is what the makers publish, lined up and read closely. How we decide what to recommend is in our method.
Common questions
What is the mattress firmness scale?
It is a 1 to 10 rating that mattress makers use to describe how soft or firm a bed feels, with 1 the softest and 10 the firmest. There is no universal standard behind it. Casper says so on its own blog, and so does PlushBeds, so each number is the maker's own judgement rather than a measurement.
What number is a medium mattress?
It depends on the maker, and sometimes on the model. PlushBeds alone rates its Medium as 5 on the Eco Bliss, 5.5 on the Botanical Bliss and 7 on the Natural Bliss. Treat the word as a range around the middle of the scale and read the number on the same brand's page.
Can you compare firmness numbers between brands?
Not reliably. Every maker sets its own scale, so one brand's 7 is not a measured match for another brand's 7. A number is most useful for ranking one maker's own models. Across brands, compare the layers instead: what sits above the support, and whether it is soft foam, latex or coils.
What is ILD on a mattress?
ILD, short for indentation load deflection, is a lab figure for how much force it takes to press a piece of foam or latex down. Higher means firmer. It describes one layer, not the whole bed, and the same maker can print it differently: one PlushBeds topper page lists its Extra Firm as 44 ILD and as 40 to 42 ILD.