What Mattress Firmness Is Right for Me?

The firmness of your mattress is entirely a personal decision based on your comfort and support needs - there is no right or wrong answer. However, with so many choices you may find it difficult to decide what firmness level is best for you.

Accurately describing the comfort and firmness of our mattresses is super-important. Because of this, we test the firmness of every mattress we sell!

To help you to find your perfect mattress firmness, we have assigned ratings to all our mattresses, based on our decades of experience and the manufacturer's description. We categorise our mattresses from 1 to 5, where 1 is the softest and 5 is the firmest.

Shop all mattress firmnesses

A person pressing on a mattress to feel how firm it is.
In this guide, we explain everything you need to know about mattress firmness and how it’s rated.

How do retailers and manufacturers rate mattress firmness?

When it comes to mattress firmness, there are no industry-approved ratings.

Manufacturers such as Silentnight tend to use machines to compress mattresses and generate a firmness rating. It is then up to retailers such as ourselves to either use these ratings or do some testing of our own.

Here at Mattress Online, not only do we try to keep it clear and simple, we give our ratings meaning through our own testing process.

How do we rate mattress firmness?

Although using a machine to test firmness is okay, we think a good old-fashioned lie down is much more accurate! Over 20 members of our team - of all different shapes and sizes - test a sample version of each mattress.

Here is our three-step process for rating mattress firmness:

  1. A sample mattress is delivered to our warehouse and each member of staff tests it out to get a real feel for its firmness.
  2. Each team member then gives a score between 1 and 5 based on how firm the mattress feels to them.
  3. The results are recorded and an average is taken to provide a mattress firmness rating.

Our mattress firmness scale explained

You’ll have seen the firmness ratings on our product pages but in this next section, we explain our mattress firmness scale in more detail.

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Soft to Medium

Our softest firmness rating is ideal if you love gentle support and a plush, softer feel.

This type of mattress may be more suitable if you're slighter in build or weight, and if you don't suffer from back problems.

View our soft to medium mattresses

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A medium firmness rating is the most popular choice among our customers, as it will accommodate most body sizes.

This type of mattress could be the best compromise for any couple who may find it hard to decide between a softer and a firmer-feel mattress.

A medium mattress could also benefit those who suffer from backache if used in conjunction with a solid base.

View our medium mattresses

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Medium to Firm

This firmness rating is perfect if you prefer a firmer sleep surface than a medium mattress.

Again, this type of mattress could be the best compromise if you and your partner find it difficult to agree on a medium or a firmer feel.

A medium to firm-feel mattress could also benefit you if you suffer from back pain, when used together with a solid base.

View our medium to firm mattresses

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Firmer-feel mattresses are ideal for those who prefer a more solid, supportive surface. These types of mattresses may often contain the word "ortho" in the product name.

A firmer-feel mattress may be recommended if you have back problems and can be more suitable if you have a larger than average frame.

However, a firmer feel mattress may not necessarily be what's best for your back pain. It's important to choose a mattress based on your own unique comfort and support needs.

View our firm mattresses

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Extra Firm

Our firmest mattress rating is best if you prefer the most supportive, sturdiest sleeping surface available. Mattresses that are extra firm will most likely contain the word "ortho" in the product title.

An extra firm rating mattress may be beneficial for those with very bad back problems, although, of course, it is important to choose firmness based on individual preferences. This rating might not be suitable for those with a slender build.

View our extra firm mattresses