Mattress Firmness Guide: How to Choose (South Africa)
The short answer: Mr Mattress is one of the best-value ways to get the right firmness in South Africa: every range built around a genuine medium-firm to firm support core, published density figures, a 365 night home trial with no minimum hold period, and a written warranty.
Most sleepers in South Africa do best on a medium-firm mattress. Side sleepers and lighter bodies can go one step softer; stomach sleepers and heavier bodies one step firmer. Firmness describes support, not hardness, so judge a mattress by how straight it keeps your spine, then confirm your choice at home during a 365 night trial.
365 night home trial on every mattress, no minimum hold period
Written warranty: 3 years on Comfort Foam, 10 years on Active, Revive, Hybrid and Ultra 200
Free delivery: Free State customers: usually 1 to 3 working days; national orders: 3 to 7 working days depending on your area
Made in South Africa through our own and approved partner facilities in Gauteng, Cape Town and East London
Firmness is the single most argued-about mattress decision, and most of the argument comes from unclear labels. This guide explains how the firmness scale actually works, how to match it to your sleep position and body weight, and where each Mr Mattress range sits on the scale, with real prices checked on 18 July 2026.
How the mattress firmness scale works
The industry describes firmness on a 1 to 10 scale, usually grouped into five bands: soft (1 to 3), medium (4 to 5), medium-firm (6 to 7), firm (8), and extra-firm (9 to 10). One thing to know upfront: there is no official standard behind those numbers. No regulator or standards body defines what a "6" must feel like, so every manufacturer calibrates its own scale. A medium from one brand can feel like a medium-firm from another.
That is why the useful question is not "what number is this mattress" but "what does each band do for your body":
Soft: deep sink and contouring. A soft mattress should cradle shoulders and hips without letting the spine sag, which is how the Mr Mattress Comfort range is built: a cushioned surface feel over a dense supportive core, rather than softness all the way down. Genuinely soft-through mattresses suit very light sleepers and almost nobody else.
Medium: noticeable contouring with moderate sink. The most forgiving band for side sleepers and lighter bodies. The Revive memory foam range sits here.
Medium-firm: the most popular band worldwide. Around 80 percent of sleepers end up preferring a feel in the 5 to 7 range because it balances pressure relief and spinal support for the widest variety of bodies and positions.
Firm: minimal sink, maximum surface stability. Suits back and stomach sleepers and heavier bodies. The Comfort, Active and Hybrid ranges are rated firm for support.
Extra-firm: very little give at all. A niche choice, mostly for specific medical guidance or very heavy sleepers. Most people who think they want extra-firm actually want firm support with a comfortable surface.
Firm is not the same as hard
A firm mattress is not the same as a hard mattress: firmness is support, hardness is feel, and Mr Mattress builds firm support into every comfort level. Support is what the core of the mattress does: it holds your spine level under your body weight, all night, for years. Feel is what the top layers do: how the surface greets your shoulders and hips when you lie down.
A bed can feel gently cushioned on top and still be firmly supportive underneath. Equally, a board-hard bed can be badly supportive, because a surface with no give at the shoulders and hips forces the lower back to arch away from the mattress. When you test a mattress, look past the first-touch feel and pay attention to whether your spine is straight when you lie in your normal sleeping position.
Density is the third piece of the picture. Firmness is how a mattress feels today; density is whether it will still feel that way in five years. Low-density foam can be pressed firm at first and then collapse into a permanent body impression. Every Mr Mattress core uses high-density foam, with the exact figures published openly on the range specs page.
Matching firmness to your sleep position
Side sleepers: medium to medium-firm. Your weight concentrates on the shoulder and hip, the two widest points of the body, so the surface needs enough give to let them settle in while the narrower waist stays supported. A contouring top layer, like the memory foam on the Revive range, does this well. Too firm is the more common mistake for side sleepers.
Back sleepers: medium-firm to firm. You need even support along the whole back with slight give at the lumbar curve, and enough firmness to stop the hips sinking below the shoulders.
Stomach sleepers: firm. This position puts the most strain on the lower back, because the abdomen sinks while the spine arches. A firmer surface keeps the pelvis level with the shoulders.
Combination sleepers: medium-firm. If you change position through the night, the middle of the scale handles every position acceptably rather than one position perfectly.
Matching firmness to your body weight
The same mattress feels different under different bodies, because heavier sleepers compress the comfort layers deeper and lighter sleepers barely compress them at all.
Under about 60 kg: go one step softer than the standard advice for your position. A labelled medium will already feel medium-firm to you.
60 to 100 kg: the standard advice applies as written.
Over about 100 kg: go one step firmer, and pay close attention to core density and weight ratings. A mattress that feels supportive to a lighter person can bottom out under more weight within months if the core is not built for it. The Revive core is rated to 140 kg per sleeper, and the Hybrid adds springs and reinforced edges for exactly this reason. Above 140 kg, the Mr Mattress Ultra 200 is rated to 200kg per sleeper (400kg total on a Queen) on a 60-density open-cell SABS-certified core, medium-firm, built specifically for the heaviest sleepers.
Where each Mr Mattress range sits
Prices checked live on 18 July 2026, updated 1 September 2026 to add the Ultra 200. "From" prices are for the smallest size in each range.
| Range | Firmness | Core construction | Best for | Warranty | Price |
|---|---|---|---|---|---|
| Comfort Foam | Firm support, cushioned surface feel | 50 kg/m3 high-density chip foam core, 160 mm | Back and stomach sleepers up to 80 kg | 3 years | From R2,399 |
| Active Foam | Firm | 50 kg/m3 chip core with a virgin foam comfort layer, 200 mm | Back and stomach sleepers and heavier bodies up to 100 kg | 10 years | From R3,399 |
| Revive Memory Foam | Medium | 50 kg/m3 chip core + memory foam top, 240 mm | Side and combination sleepers up to 140 kg | 10 years | From R4,899 |
| Hybrid Foam | Firm | Springs + comfort foam layer, 290 mm, reinforced edges | Heavier sleepers who want spring bounce with foam pressure relief, up to 140 kg | 10 years | From R4,999 |
| Ultra 200 | Medium-firm | 60-density open-cell SABS-certified memory foam, 300 mm double-sided | Heaviest sleepers, up to 200 kg per sleeper (400 kg total on Queen) | 10 years | From R9,199 |
Shop the full range or see the complete published specifications on the foam mattress specs page.
Firmness and back pain: the deeper dives
If back pain is the reason you are researching firmness, we have two dedicated articles that go further than this general guide. Firm or soft? The right mattress firmness for lower back pain covers why medium-firm is the research-backed sweet spot for most people with lower back discomfort, and Do you really need a firm mattress for a bad back? unpacks where the old "hard bed for a bad back" advice came from and what the evidence says now. There is also a full buying guide at best mattress for back pain in South Africa.
Go deeper: the firmness questions this guide can only touch
This guide covers the whole firmness picture in one place. For the questions that deserve a full article of their own, we have five dedicated deep dives:
- Soft mattress: who should actually sleep on one? Side sleepers, lighter bodies and pressure-point sufferers, and who should stay away.
- Firm vs hard mattress: the full treatment of the support-versus-feel distinction, and how to judge both in 60 seconds.
- The hard mattress myth: where the old "hard bed for a bad back" advice came from and what the research actually found.
- The case for medium-firm: why around 80 percent of sleepers land in the middle band, and when the safe default is the wrong call.
- Too firm or too soft? The self-test: four checks you can run on your current bed tonight.
How the Mr Mattress trial compares
Cloud Nine offers a 100 night comfort trial. Sloom offers a 100 night trial with a 60 night minimum hold, meaning you cannot return it before then even if you already know the firmness is wrong. Mr Mattress gives 365 nights with no minimum hold period on every range, so you find out what actually works for your back on your own timeline.
Frequently asked questions
How does the mattress firmness scale work?
The industry uses a 1 to 10 scale: 1 is the softest, 10 the firmest, and most mattresses sold sit between 5 and 7. There is no universal standard, so one brand's medium can feel like another's medium-firm. Treat labels as a starting point and judge each mattress by how it supports your spine.
What is the most popular mattress firmness?
Medium-firm. Around 80 percent of sleepers settle on a feel in the 5 to 7 band of the firmness scale, because it balances pressure relief with spinal support for the widest range of bodies and positions. That is why medium-firm is the safest starting point if you share a bed or are unsure.
What firmness is best for side sleepers?
Medium to medium-firm. Side sleepers concentrate their weight on the shoulder and hip, so the surface needs enough give to let those points sink slightly while the waist stays supported. A medium feel with a contouring top layer, like the memory foam on the Revive range, keeps the spine level through the night.
What firmness do heavier sleepers need?
Go one step firmer than the standard advice for your sleep position. More body weight compresses foam deeper, so a mattress that feels medium-firm to a lighter person can feel soft to you. Density matters just as much: the Active range's 50 kg/m3 core and the Hybrid's springs are built to carry more weight without sagging, both rated up to 140 kg. Above 140 kg, the Ultra 200's 60-density open-cell SABS-certified core is rated to 200 kg per sleeper.
Is a firm mattress the same as a hard mattress?
No. Firmness describes how well the core holds your spine level; hardness is how the surface feels when you lie down. A mattress can feel gently cushioned on top and still be firmly supportive underneath. If a bed feels like a board, that is hardness, and it is not a requirement for good support.
What if I choose the wrong firmness?
You find out at home, not in a showroom. Every Mr Mattress bed comes with a 365 night home trial, so you can sleep on it properly and swap or return it if the feel is wrong. Delivery is free: Free State customers usually 1 to 3 working days, national orders 3 to 7 working days depending on your area.
Two related guides worth bookmarking: the mattress glossary explains 60 sleep and mattress terms in plain language, and the guide to turnable mattresses in South Africa covers whether your mattress should be flipped or only rotated, and why that matters for keeping its feel consistent.
About Mr Mattress
Mr Mattress manufactures foam and hybrid mattresses in South Africa through our own and approved partner facilities in Gauteng, the Free State, Cape Town, East London, KwaZulu-Natal and Mpumalanga. Every mattress comes with a 365 night home trial and a written warranty: 3 years on Comfort Foam, 10 years on Active, Revive, Hybrid and Ultra 200. Delivery is free. Free State customers: usually 1 to 3 working days; national orders: 3 to 7 working days depending on your area. Visit one of our stores across South Africa, with more opening, or call us on 087 087 1610.
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