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The right firmness depends mostly on how you sleep and how much you weigh. Answer four questions for a firmness range on the standard 1–10 scale, a mattress type and the pillow height that keeps your spine aligned.
Firmness by sleep position
| Sleep position | Firmness (1–10) | Pillow loft |
|---|---|---|
| Side | 4–6 (medium-soft to medium) | High — fills the gap between ear and shoulder |
| Back | 5–7 (medium to medium-firm) | Medium |
| Stomach | 6–8 (medium-firm to firm) | Low or none |
| Combination | 5–7 | Adjustable fill |
Heavier sleepers generally need about one point firmer; lighter sleepers about one point softer.
FAQ
What firmness is best for back pain?
Research generally favors medium-firm over very firm mattresses for lower back pain. Very soft beds let the hips sink and bend the spine.
Why do firmness ratings differ between brands?
There’s no industry standard — one brand’s 6 can feel like another’s 7. That’s why a long home trial matters.
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