What “Firmness” Really Means in the Mattress World

Firmness is a tricky topic in the world of mattresses.

You wouldn’t think it would be, but it is.

It can sometimes seem like every mattress company has their own way of looking at it.

Some use a scale from 1 to 10.

Others use a more subjective spectrum between “soft” (or “plush”) and “firm.”

Still other companies don’t even mention firmness in their mattresses at all, claiming a “universal comfort” that will meet the needs of almost every sleeper.

What Are We Supposed to Do with All This?

What does “firmness” even mean, when everybody seems to be working with a slightly different idea?

This isn’t the kind of thing you can just brush aside, either—finding the proper firmness in your mattress is one of the most important parts of choosing the right product for you, and it really pays to get this one right.

You spend a third of your life on a mattress.

It’s worth your while to know what you’re getting into.

So, here it is—your complete guide to mattress firmness.

Stop being confused, and start sleeping right!

Defining Mattress Firmness

At the most basic level, “firmness” just refers to the amount of resistance pushing back against your body when you lie down on a mattress.

But the thing is, there’s no object measurement for what that actually means.

It’s all about how the mattress feels against your body—how much give it has, what the experience of lying down on it is like.

There is technically no official industry standard for what a mattress’s firmness level is, although many of them use similar terms to talk about similar properties of their product, especially when they offer a range of different firmness levels.

Obviously, “soft” or “plush” means a mattress will have more give than a mattress labelled “firm” or “hard.”

They might also give a firmness rating for their mattress somewhere on a scale from 1 to 10.

Third-party sites like us will often take the subjective words like “soft” and “firm” and convert them to measurements on that scale, so you can pretty easily compare how firm different mattresses are.

Still, though, we’d be lying if we said there wasn’t a bit of uncertainty to the whole measuring process.

Also keep in mind that there’s no way to know exactly how you’ll feel on any given mattress until you physically lie on top of it.

One person’s firm is another’s plush, and vice versa.

Still, we do our best.

By looking at measurements on the 1 to 10 scale you can be pretty confident on how firm different mattresses are relative to each other, so you should probably be able to figure out a good idea of what they’ll feel like to sleep on.

A Note on Memory Foam Mattress Firmness

For the sake of simplicity, we’re mostly going to be talking about innerspring mattresses in this article.

Full disclosure, though – memory foam firmness actually works a little differently, and there are some objective measurements you can look at there.

It’s just complicated, and a story for another time.

Finding Mattress Firmness on This Site

Now, before we get too much further along talking about mattress firmness, it’s worth mentioning that here at Ted and Stacey’s Mattress Guides, we really do try to take the mystery out of mattress firmness.

It’s one of the first things we talk about on all of our reviews, and you’ll often be able to find a very in-depth description of what it feels like to sleep on the particular mattress you’re looking at.

So while it’s definitely useful to have a solid baseline understanding of how mattress firmness works, we do everything we can to remind you of the important bits of information when you’re browsing through our mattress reviews.

With that in mind, let’s now move on to…

The 1 to 10 Scale of Mattress Firmness

On this site, we mostly look at mattress firmness on a scale from 1 to 10, with 1 being the softest and 10 being the hardest.

Again, this scale isn’t 100% subjective, but it is pretty dang good for the layperson trying to figure out their next mattress purchase.

Before we get into the specifics of this, it’ll be helpful to realize that most mattresses will fall somewhere between a 5 and a 7 on this scale.

These mattresses will work for about 80% of all people. 

1 to 2: Ultra Soft

A mattress between a 1 and a 2 on the firmness range is almost ridiculously soft.

You’ll get basically zero support on a mattress like this.

Just about any sleeper will easily sink past the comfort layers on top of an innerspring, likely hitting the support core.

Virtually no mattresses are rated 1-2 on this scale, and there’s a reason for that – most people would find them extremely uncomfortable.

3 to 4: Soft

Sometimes called “plush” or “extra soft,” mattresses rated between a 3 and a 4 on the firmness scale have a very high degree of sinkage – usually 1.5 to 3 inches.

These mattresses can be fantastic for side sleepers, but they’re typically not recommended for any kind of stomach or back sleeper, since they simply will not give the kind of support you need.

Innerspring mattresses of this type are usually pillow-tops, or they may simply have thick traditional padded covers.

They may also have deep contour memory foam.

Either way, these mattresses are primarily recommended only for side sleepers.

5 to 6: Medium

Most people prefer mattresses somewhere on this range, with 6 being by far the most popular firmness level.

Sixes in particular offer a very balanced feel, with good support and moderate sinkage.

Level 5 firmness—“medium-soft”—Is actually a little on the softer side, although it’s smack dab in the middle of the scale.

Most sleepers will feel right at home on either a 5 or a 6. 

7 to 8: Firm

Mattresses at this level offer more pushback and less hug or sinkage than medium mattresses.

Sevens, or “medium-firms” are still good for most people.

Once you get to level 8, though, side sleepers will start having a pretty rough time of it.

They’re usually only appropriate for stomach or back sleepers.

9 to 10: Extra Firm

Very few mattresses fall within this range.

They offer extreme pushback and practically no give.

Although there are some therapeutic mattresses at level 9, almost nobody makes a level 10 mattress.

They’re just not comfortable for the vast majority of people.

Staying Informed on Mattress Terms

Note that some companies might use slightly different words to describe their product than what we’ve listed here.

You might find “slightly firms” instead of “medium-firms,” or “medium-plush” instead of “medium-soft.”

This is mostly just semantics.

The descriptions we’ve provided here will give you a good idea of what you’re getting into when you see us assigning a number to a mattress’s firmness on our reviews.

What Is a “Universal Comfort” Mattress?

Some mattress companies try to get around all the confusion of the different levels of mattress firmness with what they call “universal comfort” mattresses.

Obviously, this is a bit misleading – no mattress firmness is going to be right for everyone.

Still, these mattresses are usually a pretty good fit for most people.

They’re almost always somewhere between a 5 and a 7 on the firmness scale, and you can see the specific numbers of our reviews.

That’s actually one of the big advantages of having a look at our reviews of specific mattresses, in that you’ll sometimes get more information than you’d be able to find on the mattress company’s website itself.

A lot of companies will try to pass themselves off as if they’re the perfect fit for everyone, but we know that’s really not the case.

Everyone has their own wants and needs – “universal comfort” is just a marketing term.

Mattress Firmness vs Support

When we’re talking so much about firmness, it’s sometimes easy to get mixed up with another, related term: support.

Firmness and support are not the same thing.

Again, firmness refers to the tactile sensation of lying on the mattress.

It’s your personal take on how hard or soft the surface is.

Support, on the other hand, refers to how good the mattress is at keeping your spine in alignment. 

You want a mattress that gives you an appropriate level of firmness and as much support as possible.

To be fair, most firm mattresses do, in fact, offer good support.

But that’s not true of all of them, and you certainly shouldn’t spring for a firmer mattress just because you’re looking to ease your back pain.

If you’re looking a mattress like that, you should check out our complete article.

How Do I Know if I’ve Found the Right Mattress Firmness?

Figuring out if you’ve found the right mattress firmness level is a complex process as sleep position and body weight are only part of the factors.

Most importantly, it just takes being honest with yourself about the way you feel when you lie down.

Never settle for pain or discomfort.

Conclusion About Mattress Firmness

Hopefully this article was helpful in understanding the crazy world of mattress firmness.

We know it’s not always the easiest or most intuitive system to work with.

That’s what we’re here for, though.

We want to help you make the most informed decision you can about your future mattress.

So even if the wacky marketing tactics of these companies get you going crazy sometimes, always remember that we’re here for you.

We want you to get the best mattress you possible can.

Don’t get thrown by tricky tactics.

Just keep learning and researching, and you’re sure to find the best mattress for you.