Mattress Firmness Guide

Mattress comfort tailored to individual needs.
Mattress Firmness Guide
Tom Greenspan
December 21, 2022

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How do you go about selecting the right mattress for you? We spend around a third of our lives sleeping, so the right mattress is critical if we are to get rejuvenating, restful sleep. There are so many factors when it comes to buying a mattress; the choice is so varied it has become a minefield with a lot of information to absorb before you even venture out to find a mattress. Density, edge support, motion isolation, how can you ever know if you have the correct mattress for you? Well, one way is to focus on the firmness of the mattress and on how much support you need. Your body weight plays a significant factor in choosing the right mattress, and if you sleep hot because you carry some extra pounds, the choice can be difficult.

This article investigates mattress firmness and how you can use the mattress firmness guide to evaluate the type of mattress that is best for you. We answer frequently asked questions and provide factual information to help you decide on your mattress.

Let's get into it.

What is the mattress firmness guide?

As you may have guessed, the mattress firmness guide is precisely what it says. It's a guide that the industry has used to help potential buyers of mattresses understand the firmness or softness of a mattress. Don't get the firmness guide misconstrued with mattress density. They may be related to the subject, but nuances separate the two factors.

One of the most crucial aspects to take into account when deciding to buy a new bed is mattress firmness, which relates to a mattress's cushioning. Your bed's initial feel and how much pressure is relieved to depend on how firm it is. The majority of mattress manufacturers rate mattress hardness on a scale of 1 to 10, with 1 being the softest and 10 being the firmest.  A little bit of your own tastes play a role in selecting the proper firmness level, but your body weight and sleeping posture play the most prominent roles.

Mattress Firmness scale

You can see there is not any ambiguity in the way the scale is set out, it is based on body weight and the preferred sleeping position.

Soft 1-2

The most cushioning of any mattress is provided by soft mattresses, which range from a 1 to a 2 on the mattress scale. Your body sinks into plush mattresses, which closely encircle it. The ideal mattress for people with less weight to support and side sleepers is often soft. While petite sleepers require a softer bed to properly cushion the body because it doesn't put as much pressure on the bed, side sleepers need the extra cushioning to prevent pressure points on the stomach and hips.

However, there can be too much sinkage and contouring. Very soft mattresses are, therefore, typically rare. In reality, most mattresses advertised as soft are more medium than soft.

Medium-soft 3-4

Soft mattresses are far less prevalent than medium-soft mattresses, which range from 3 to 4 on the firmness scale. In order to prevent sinking and feeling trapped in bed.  Medium-soft mattresses still closely conform to your body but are more durable and have a thinner comfort layer than soft mattresses.

For people who need padding to minimize pressure buildup but also don't want to feel trapped in their bed, as they could on a soft mattress, medium-soft mattresses are an excellent alternative.  In general, adults who sleep on their sides and are 130 lbs and less do well with medium-soft mattresses. It is a good mattress for a young adolescent.

Medium 5-6

Medium mattresses, which range in firmness from 5 to 6, offer the perfect amount of support and cushioning. Because they work for so many different people, they are a very popular mattress firmness. Nearly all companies, even those with few mattress options, will provide a medium mattress. Medium mattresses are supportive enough to accommodate multiple postures while not being too cushiony to make movement difficult for those of you who frequently change positions during the night.

Medium-sized beds are the finest mattresses for couples with various body shapes and sleeping positions.  Additionally, medium mattresses are still soft enough for small people to utilize without discomfort.

Medium firm 7-8

The firmness of medium-firm mattresses ranges from 7 to 8, and they offer just enough cushioning so that you may sleep soundly without sinking into the mattress. Most of the time, a medium-firm bed is most comfortable for back sleepers. Additionally, a medium-firm mattress is firm enough to prevent sinking in your bed if you weigh more than 230 pounds. 

In addition, medium-firm mattresses are an excellent option if you experience persistent back pain to reduce your suffering.

Firm 9-10

The stiffest and firmest beds are those with solid mattresses. Both their base layers and comfort layers are pretty thin. Extra hard beds (10) are not as hard to find as soft beds as extra soft beds (1). Most individuals find extra firm mattresses to be a little too rigid, and they run the risk of making you uncomfortable with aches, pains, and pressure points.  The more typical mattresses are standard firm, such as (9).

Although some individuals might assume that the word "firm" indicates discomfort, firm beds can be comfortable. It depends on your size and sleeping posture whether you'll be comfortable on a firm bed. Body weight dictates so much about comfort. A firm bed will compress and feel comfortable to those of you who carry more pounds.

In order to support their bodies and keep the bed from bottoming out, larger sleepers typically require a firmer sleeping surface. Similar to side sleepers, back and stomach sleepers require a firm bed to avoid their lower backs and spines sinking and misaligning their spines.

Sleeping with a partner

If you share a bed, you must also consider your bed partner's needs, particularly if they require a different level of firmness, to ensure you are both comfortable. A split king-size mattress is ideal for couples since it allows you and your companion to select different hardness levels without worrying about motion transmission. 

Split king mattresses are an option, but not everyone can afford them or use them because they need particular accessories. For the majority of sleepers, a medium mattress offers a good blend of support and comfort and is the best compromise when sleeping with your partner.

Is there a difference between firmness and support in a mattress?

Although support and firmness may appear to be the same thing, they are not. While support refers to how well your bed aligns your spine, firmness affects how your bed feels. It's a common miscalculation that firm mattresses are uncomfortable and stiff, while soft mattresses sag easily and are unsupportive. Premium quality firm mattresses can be comfortable, while high-quality soft mattresses can be supportive and long-lasting.

Therefore, don't assume hardness and support are corresponding when choosing a mattress. To ensure your mattress is supportive and comfortable, keep both in mind.

Does the firmness of the mattress affect your sleeping position?

Your preferred mattress firmness is most influenced by how you sleep. Your preferred sleeping position affects your possible pressure points, level of discomfort, and amount of contouring required.

Side sleepers

Medium-soft to medium-firm mattresses are ideal for people who prefer to sleep on their sides. The thick comfort layers should cushion the shoulders and hips, two locations prone to pressure points when resting on one's side.

Back sleepers

Back sleepers should choose medium- to medium-firm mattresses. The right amount of support and padding encourages optimal spinal alignment without creating too much sinking.

Combo Sleepers

For mixed sleepers, medium or medium-firm beds are ideal. The two mattresses' balanced feel will adequately support most sleeping positions.

Tummy sleepers

The ideal mattress for stomach sleepers should be firm or medium-firm. More substantial mattresses prevent your hips from sinking, resulting in lower back pain.

Does body weight influence mattress firmness?

Your weight impacts how much pressure you put on your bed and how the mattress feels under you. As a result, differing levels of support are needed for light and heavy sleepers. Most mattress manufacturers base their firmness rating on a typical consumer, who weighs between 130 and 230 pounds and is of average height.  If you're not an adult of average size, you might be unsure which firmness you need.

A springy mattress may be preferable for heavier sleepers so they can move around more easily and prevent sinking in when lying down.  Many people opt to try a more recent hybrid mattress because traditional innerspring mattresses can have a mixed reputation regarding cushioning materials and full-body pressure reduction.

Frequently asked questions

Is there a universal firmness, one size fits all mattress?

While the term universal may be attractive, and a one size fits all option will remove the headache of buying a new mattress, in some respects, it's a marketing ploy on behalf of the retailer. While this typically means the mattress is around a medium or medium-firm firmness, some brands describe their mattresses as "universally comfortable" (5 to 8 on the firmness scale).

There isn't a mattress that "fits all," despite how alluring a universal comfort mattress may seem, because it might make selecting a mattress firmness less stressful. Despite the fact that medium and medium-firm mattresses balance comfort and support.

Is there the best firmness for a mattress?

Because firmness is a personal preference, there is no one optimal firmness for a mattress. Your body type and preferred sleeping position will determine your ideal firmness. From there, you can select the stiffness that is best for you.

Does changing your mattress cause back pain?

It is possible. It is recommended to change your mattress every 8 years. Sleeping on a sagging mattress is clearly bad for your posture, and when you change to a new memory foam mattress, the posture change will be significant. Back pain can arise from a new mattress. That's because switching from an old, ineffective mattress to a new, supportive mattress requires some adjustment time. 

There's a break-in period for new mattresses as well. Over time, components will soften and adjust to your body after being rigid. Your back must become used to a new mattress over time. If you've used the same mattress for years, your body may be accustomed to it. Therefore, switching to something better for your back may not feel the best initially.

Do mattresses get softer over time?

Yes. However, this does not imply that your new mattress will become noticeably softer after just a few months of use. Instead, your mattress will soften and get lumpy as it gets older after being used for a while, and you'll eventually need to replace it. Although mattresses typically last between 7 and 10 years, the longevity of your mattress will depend on the type of mattress you have—memory foam latex, hybrid, etc. 

This means that the firmness of your mattress has no bearing on how long it lasts.

How can you know if your mattress is too hard?

If it's a new mattress, it's essential to sleep on it nightly and break it in for at least days and maybe longer. If you wake with the following symptoms after a couple of months, the mattress may be too hard for your sleeping style and body weight:

  • You experience hip, shoulder, or back pain when you awaken.
  • You're worn out when you wake up.
  • Your hands and arms are tingly or numb.
  • Your mattress is not shaped to fit your body.


It takes some searching to find comfy solutions that will suit your demands and fall within your budget while looking for mattresses.  So be diligent, do your research, and don't be scared to comparison shop. The result—a comfortable mattress that promotes restful sleep and increased energy—is well worth the investment.