Mattress Firmness Guide [2024]

Mattress Firmness Guide

Mattress Firmness Guide

Everyone experiences mattress firmness differently. 

It comes down to what way you sleep, body shape, body weight, and of course personal preference. Mattress firmness are measured by what exactly is in the mattress – example: Memory foam, firmer fillings, pocket springs.

DFI help customers with trying to find the right mattress firmness by creating a firmness chart with each mattress so customers know exactly which rating the mattress is with help from the firmness chart.

What is meant by Mattress Firmness?

Mattress firmness refers to how soft or hard a mattress feels when you lie on it. Every mattress will be different as the materials used inside the mattress can vary and increase or decrease the firmness.

DFIs meter has 5 different ratings of firmness. Our ratings are based on a survey of 25 Sleep Experts. The softness of a mattress is at the start of the scale and firmness at the end.

What are the basic Mattress Firmness levels?

  • Soft 
  • Medium
  • Firm

What makes a mattress firmer?

  • Pocket Springs
  • Normally the more pocket springs in a mattress can mean the firmer the mattress is. This is not always as again it comes down to the filling layers on top, but normally if the mattress doesn’t have comfort layers on top, the firmer the mattress would be while also being supportive.

  • Foam
  • When people think of foam, they automatically associate it with memory foam but the truth is foam comes in all different firmness options. Manufacturers can add firmer foam fillings into a mattress to add to the thickness and firmness of the mattress.

  • Hybrid
  • A Hybrid mattress requires both pocket springs and comfort layers of foam. This means it would be a combination of pocket springs and foam which means it can come in a wide range of different firmness levels.

    Understanding the mattress firmness scale

    Below you will see the DFI Mattress Firmness Meter that we use in each spec of mattress. Our scale has 5 different ratings, soft, soft-medium, medium, medium-firm and firm.


    DFI Mattress Firmness Chart


    Sometimes customers find it difficult to understand the scale and the difference between soft and soft-medium or medium-firm to firm.

    We recommend thinking of the scale as numbers 1-10.

    Mattress Firmness Scale

    Firmness 1-2: Soft

    A mattress of this rating means the mattress itself it more than likely to be made up on memory foam. The mattress would shape to the sleepers body shape a lot more quickly and provide a sink in feeling when sleeping on it. Depending on the sleeper’s body shape and weight, this would not be recommended for a heavy body as the mattress will show a lot of settlement and it wouldn’t last the guaranteed years because of this. 

    Firmness 3-2: Soft medium

    Slightly firmer, this rating of mattress would be made up with a soft surface top, and have the support of minimum springs but would still mould to the sleeper’s body shape providing a sink in feeling on top of the mattress. 

    Firmness 5-6: Medium

    Medium mattresses use more pocket springs than the softer mattresses and start to provide different types of foam to give a firmer filling, these mattresses do intend to sink less but can still mould to your body shape more quickly.

    Firmness 7-8: Medium-Firm

    Medium – firm mattresses sink less as there are more pocket springs than memory foam fillings in the mattress itself. This means more support, more thickness and more firm than a mattress with memory foam layers. There would be minimal dipping in this mattress due to firmness of this mattress but will still provide a comfort layer so you have the best of both worlds, not too soft but not the firmest one either.

    Firmness 9-10: Firm

    Firmer mattresses normally means there are no memory foam in these mattress and they are made up of springs and firmer fillings. There is little to none dipping in these mattresses as it would be very hard to mould to your body shape with the firmness of the mattress. Mattresses with this rating has great support and tend to last longer also as there would be very little sinkage.

    What kind of sleeper needs a firm mattress?

    • The most popular sleeper that requires a firm mattress is a back-sleeper. The firmer mattress provides pressure relief for back and joints. It is provides even distribution of weight and promotes spinal alignment which works out perfect for a back sleeper. For more advice on this, please see our post on The Best Sleeping Positions.
    • A person with a bad back would also need to look for a firm mattress, having a firm mattress with pocket springs means it offers maximum support and designed to spread your body weight evenly. It targets pressure points and helps with back, hips and joints. For more advice on this, please see  our post on the Best Sleeping Positions for Back Pain.
    • A heavier person should go for a firmer mattress as a soft one would leave them feeling like they are ‘sinking in’ to the mattress and wouldn’t help with their sleep, back pain etc, just like a person with a lighter weight would tend to go for softer mattresses as a medium to firm mattress may be too hard for themselves. For much advice on this, please see The Best Mattress For Heavy People


    How to choose the right firmness for you?

    I would advise customers to really have a think before purchasing their mattress, take into consideration all points in this blog, think about what kind of sleeper you are, body shape and weight, if you are sleeping alone or with a partner or kids. 

    The most popular choice is Medium firmness as customers tend to stay in the middle when it comes to choose firmness and lucky for you, we have a lot of medium firmness mattresses.

    See our daily offers and speak to sleep experts and get REAL advice and feedback on what is best for you.

    Brian McCann

    Our Managing Director Brian's expertise in crafting comfortable sleep experiences makes him a reliable voice for all things bedding-related. Brian publishes advice and tips on mattresses, beds and the overall sleep experience based on extensive industry experience.

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