How to choose mattress firmness
Updated 10 January 2026 · 5 min read
Firmness is the single most confusing part of mattress shopping, because there is no industry standard behind the words on the label.
Why one brand's medium is another's firm
Each manufacturer sets its own scale. One brand's 'medium' can feel firmer than another's 'medium-firm', and retailers sometimes relabel the same mattress differently.
We store the manufacturer's own wording exactly as published, and separately record a normalised firmness rating so mattresses can be compared with each other.
Start from your sleeping position
Side sleepers usually want more give so the shoulder and hip can settle without twisting the spine.
Back sleepers tend to do best in the medium to medium-firm range. Front sleepers usually want firmer support to stop the hips dropping.
Body weight changes the feel
The same mattress feels softer to a heavier person and firmer to a lighter one, because firmness describes how much a surface compresses under load.
If you and your partner are very different weights, a mattress with a supportive core and generous comfort layers usually works better than picking a firmness in the middle.
Use the trial period
No amount of reading replaces sleeping on a mattress for a few weeks. A 100-night trial is a genuinely useful feature, not just marketing.
Check who pays return postage and whether the mattress has to be unmarked, before you rely on the trial.
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