Quick answer: There is no single firmness that is best for everyone. Medium-firm is a sensible place to begin for many shoppers, but your sleep position, body build and preferred feel determine whether you should compare something softer or firmer. The goal is a mattress that cushions the areas pressing into it without letting the rest of your body settle uncomfortably.
If you have ever tried two mattresses carrying the same “medium-firm” label and wondered why they felt completely different, your body was not imagining it. Mattress firmness is not standardized across brands. The cover, comfort layers, spring or foam core, zoning and even showroom use can all change how a model feels.
That is why Canadian Mattress scores mattresses on a consistent 1–10 comparison scale across our own lineup. The number is not a medical grade or an industry-wide standard. It is a practical way to compare one mattress with another before you test them online or in person.
Firmness and support are not the same thing
Firmness is the first sensation you notice: how readily the surface gives under your body.
Support describes how the complete mattress holds your body after you settle into it.
A firm mattress is not automatically more supportive. A softer comfort layer can sit over a strong support system, while a hard-feeling mattress can still be a poor match for a particular body. Research also does not support the old idea that the hardest possible mattress is healthier. In one randomized trial involving adults with chronic, nonspecific low-back pain, a medium-firm mattress produced better outcomes than a firm mattress. That result challenges “firmer is better” for that specific group; it does not establish one ideal firmness for every shopper.
The useful question is not “Is firm healthy?” It is:
Does this mattress give where my body needs cushioning while remaining stable where I need support?
How to use the Canadian Mattress 1–10 firmness scale
Think of the scale as a map for comparison:
| Range | General feel | What to pay attention to |
|---|---|---|
| 1–3: softer end | More surface give and contouring | Shoulder and hip cushioning, ease of movement, how deeply the pelvis settles |
| 4–7: middle range | A balance of give and resistance | Even contact, pressure relief and whether the mattress works in more than one position |
| 8–10: firmer end | Less sink and a flatter, more resistant surface | Shoulder and hip pressure, midsection stability and how easy it is to turn or get up |
Those bands are intentionally broad. A 6/10 pocket-coil mattress will not feel identical to a 6/10 memory-foam mattress. Use the number to build a shortlist, then compare the complete feel.
You can see the same firmness scores on participating Canadian Mattress product pages and in the mattress quiz.
Start with the way you actually sleep
Your main sleep position changes which parts of your body press most heavily into the mattress. Treat these as starting clues rather than rigid rules.
Side sleepers
Your shoulder and hip need enough room to settle without feeling sharply loaded. At the same time, the mattress should not let the pelvis drop so far that the waist feels unsupported.
Start in the softer-to-middle part of your comfortable range, then compare one option firmer. If the softer model relieves pressure but makes you feel folded at the waist, it is probably not the better fit.
Back sleepers
Look for even, comfortable contact from the upper back through the pelvis. A mattress that lets the hips settle much more deeply than the rib cage may feel unstable. A surface that is too resistant may leave an uncomfortable gap or concentrated pressure.
Many back sleepers begin in the middle range, but your body proportions and preference matter more than the category.
Stomach sleepers
Pay particular attention to whether your pelvis settles noticeably deeper than your chest. If it does, compare a firmer-feeling model. Also check your pillow: a pillow that is too tall can make a stomach-sleeping setup uncomfortable even when the mattress is reasonable.
Combination sleepers
Test every position you use, not only the position in which you fall asleep. A mattress can feel excellent on your back yet create pressure when you roll to your side. Ease of movement also matters if you change position frequently.
For a deeper construction comparison, read Mattress Types Explained: Foam, Hybrid, Pocket Coil and Latex.
Body build changes how the same mattress feels
Two people can lie on the same mattress and experience different firmness. A person who compresses more deeply into the comfort layers may experience the model as softer. A person who compresses them less may feel more of the surface resistance.
Proportions matter too. Broad shoulders, a pronounced waist, or a larger difference between the waist and hip can change where pressure and gaps develop. This is one reason fixed charts based only on body weight are too simplistic.
Use your build to decide which direction to compare:
- If you barely engage the comfort layers and notice shoulder or hip pressure, try the next softer score.
- If you move through the comfort layers quickly and feel the pelvis settling too deeply, try the next firmer score.
- If both occur, compare a different construction rather than chasing firmness alone. Zoning, layer thickness or a more responsive comfort material may matter.
What if two people share the mattress?
Do not automatically split the difference between two preferences. First determine what each person is reacting to.
One partner may say “too firm” because of shoulder pressure. The other may say “too soft” because turning feels difficult. A responsive mattress with better pressure relief may solve both complaints without landing exactly halfway on the scale.
When comparing as a couple:
- Each person should test the mattress alone in their usual positions.
- Lie down together and check whether the centre changes the feel.
- Have one partner turn or get out of bed while the other remains still.
- Compare the usable edge if either person sleeps near it.
- If your needs remain far apart, ask about split-size or adjustable options rather than forcing one compromise.
Signs a mattress may be too firm
A mattress may be worth comparing with the next softer score if:
- your shoulder or outside hip becomes uncomfortable in your usual position;
- you remain visibly propped above the comfort layers rather than settling into them;
- you keep changing position to escape one concentrated pressure point;
- the mattress feels stable but never lets your body relax.
These signs do not diagnose a medical problem. They simply tell you that the pressure response deserves another comparison.
Signs a mattress may be too soft
Compare the next firmer score if:
- your pelvis or midsection feels noticeably lower than the rest of your body;
- turning or getting out of bed takes more effort than expected;
- you feel as though you are sliding toward your partner or the centre;
- the surface feels comfortable at first but unstable after several minutes;
- you like the cushioning but want a more responsive or secure base beneath it.
Sometimes the answer is a firmer model. Sometimes it is a different construction with similar pressure relief and faster response.
A practical showroom test
You do not need to spend an afternoon lying on every mattress in the store. A controlled comparison is more useful.
1. Build a three-mattress shortlist
Start with the score suggested by the mattress quiz, then choose one nearby option softer and one firmer. Keep size and price range consistent where possible.
2. Use your normal pillow and position
Lie in the position you spend the most time in. Give each mattress several minutes. A quick sit on the edge mostly tells you about the quilt and perimeter.
3. Separate pressure from support
Ask yourself two questions:
- Where do I feel the most pressure?
- Where do I feel the least stable?
Those answers are more useful than “comfortable” or “uncomfortable.”
4. Change positions and use the edge
Roll over, sit near the side and stand up. If you share the bed, have your partner move while you remain still.
5. Revisit the finalists
After several beds, small differences blur together. Try one deliberately firmer model as a contrast reset, then return to your two finalists. The difference is often easier to identify.
Canadian Mattress’s Calgary and Edmonton teams are non-commission, so the purpose of the comparison is to narrow the field—not to push you toward the most expensive mattress.
Plan a Calgary showroom visit or visit the Edmonton mattress showroom.
What about back pain?
A mattress is not a treatment plan, and no single firmness is proven best for every cause of back pain. The best-supported general research favours medium-firm over very firm surfaces for some adults with chronic, nonspecific low-back pain, but the evidence varies and personal fit still matters.
Read Sleeping With Back Pain: What Your Mattress Can—and Can’t—Fix for a cautious guide. Persistent or worsening pain should be discussed with a healthcare professional.
Choose a starting range
If you already know the direction you prefer, compare the current:
If you are unsure, take the Canadian Mattress sleep quiz. It uses your answers and the comfort-profile data on our mattresses to create a practical shortlist. Treat the result as a starting point, then verify the fit online or in person.
Frequently asked questions
Is a firmer mattress always more supportive?
No. Firmness describes how resistant the surface feels. Support depends on the complete mattress and how your body settles into it.
Is medium-firm best for everyone?
No. In one important trial, medium-firm performed better than firm for adults with chronic, nonspecific low-back pain. That does not establish the best starting point for the general population. Sleep position, body build, comfort preference and construction still affect an individual fit.
Should side sleepers always choose a soft mattress?
No. Side sleepers often need enough surface give for the shoulder and hip, but “soft” alone does not guarantee good pressure distribution or stability. Compare the exact models.
Does a new mattress feel firmer than the showroom model?
It can. Display mattresses have been used, while some new foam layers and covers take time to settle. Room temperature, protectors and the foundation can also change the feel. See what to check when a new mattress feels firmer at home.
Can a couple with different preferences share one mattress?
Often, yes. Compare the reason behind each preference, not only the label. If the needs remain far apart, split-size configurations may be more effective than forcing one compromise.
This guide offers general shopping information, not medical advice. Persistent or worsening pain should be discussed with a healthcare professional.