Mattress Firmness Guide
How Firm Should Your Mattress Be?
Firmness is the single biggest reason a mattress feels right or wrong — and it has almost nothing to do with quality. A firm mattress is not a better mattress. It is simply a different one.
Every Betalife mattress is graded into one of five feel levels, and carries a softness number within that level. One level per mattress, one scale across the site — so once you know yours, you can shop straight to it.
What Each Level Feels Like
Each diagram shows how far your hip presses into the same mattress at each level. The levels are mutually exclusive — a mattress is never both Plush and Medium Plush.
The softest level. Deepest cushioning at the shoulders and hips — you sink in noticeably and the surface moulds to your outline.
SuitsSide sleepers, and lighter body weights.
Look elsewhere ifYou sleep on your stomach, or you dislike feeling held in one position.
Shop Plush →Soft on the surface with more support underneath. The layers below stop you sinking as far as Plush.
SuitsSide sleepers who found Plush too sinking, and side-to-back combination sleepers.
Look elsewhere ifYou wake with lower back ache — that can mean not enough support under the hips.
Shop Medium Plush →Enough give to relieve pressure, enough support to keep the spine in line. The safest choice when you are unsure, and when two people share the bed.
SuitsMost sleepers, and combination sleepers who change position overnight.
Look elsewhere ifYou have a strong existing preference — Medium is a middle ground, not a specialist.
Shop Medium →The spine is held flatter. There is still a comfort layer on top, so it is not a hard surface — you simply do not sink into it.
SuitsBack sleepers, and anyone who wants the hips held level with the shoulders.
Look elsewhere ifYou sleep on your side and feel pressure building at the shoulder or hip.
Shop Medium Firm →Minimal sink. You rest on the surface rather than in it.
SuitsStomach sleepers, and heavier body weights needing more support underneath.
Look elsewhere ifYou sleep on your side, or you are light enough that a firm surface never yields.
Shop Firm →Between two levels? Go firmer.
Comfort layers compress slightly over the first few months, so a mattress rarely gets firmer with age.
A topper can soften a mattress later. Nothing can make a soft mattress firmer.
How to read our softness number
Every Betalife mattress carries a softness number beside its level. Higher means softer — a 7 gives more than a 6, every time.
The bands mean the same thing on every product page here, so the number does one job and does it well: it ranks our mattresses against each other. Use it to separate two Medium Firms when the words alone will not.
It does not travel between brands. No industry standard sits behind firmness numbers, so another retailer’s 7 may feel nothing like ours. Compare numbers on this site; compare levels everywhere else.
The Softness Number, Level By Level
Softest at the top. The number falls as the mattress firms up — a 10 gives the most, a 1 the least. Numbers can carry a half step: a 4.5 sits inside Medium Firm, a 5.5 inside Medium.
| Number | Level | Who it suits |
|---|---|---|
| 8–10 | Plush | Side sleepers and lighter body weights who want to sink in |
| 6–7.9 | Medium Plush | Side sleepers who found Plush too sinking, and side-to-back combination sleepers |
| 5–5.9 | Medium | Most sleepers, and two people who need one bed to suit both |
| 4–4.9 | Medium Firm | Back sleepers who want the hips held level with the shoulders |
| 1–3.9 | Firm | Stomach sleepers, and heavier body weights needing more support underneath |
Firmness is felt, not measured
Your build, your weight and the way you sleep all change how the same surface reads. Two people can lie on one mattress and call it two different things — and both be right.
So use the number the way it was built to be used: to rank our mattresses against each other, not as a promise of how yours will feel on the night.
Choose By Sleep Position
Your usual position decides where your body needs to sink and where it needs to be held. The goal is always the same: a straight spine.
Choose By Sleep Position And Weight
| Sleep position | Start with | Why |
|---|---|---|
| Side | Plush or Medium Plush | Shoulders and hips must sink so the spine stays straight |
| Back | Medium or Medium Firm | The lower back needs filling in without the hips dropping |
| Stomach | Medium Firm or Firm | The hips must not sink, or the lower back arches |
| Combination | Medium | Easiest to move on, and forgiving across positions |
| Two people, different positions | Medium | The middle ground both can live with |
Then adjust for weight
Weight changes how far you press into the same mattress, so it shifts the level you need.
Under 60 kg
Plush or Medium Plush
60–105 kg
Medium or Medium Firm
Over 105 kg
Medium Firm or Firm
Firmness Questions
Still Deciding?
Our mattress buying guide covers types, sizes, care and what to look for.
Read the Mattress Buying Guide →Sleep Better, Spend Smarter
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