How High Should a Pillow Be for Side Sleepers?
When you lie on your side, your shoulder props your upper body up off the mattress. Your head has to be held up by the same amount, or your neck bends down toward the bed all night. The pillow's job is to fill that gap.
The shoulder-gap rule
A good starting point for a side sleeper's pillow height is the distance from the side of your head to the outer edge of your shoulder. You can estimate it with a simple formula:
Pillow height ≈ (shoulder width − head width) ÷ 2
For example, if your shoulders measure 42 cm across and your head is 15 cm wide, the gap is (42 − 15) ÷ 2 = 13.5 cm. That's the height your pillow should hold while your head is resting on it.
Compressed height vs. listed height
Pillow listings show the height of the pillow sitting untouched on a table. Once your head is on it, most pillows squash down by roughly a fifth to a third. Shredded memory foam and latex compress less; down and polyester fiber compress more. So if your target is 12 cm under your head, look for a listed height of around 15 cm (about 6 inches).
Your mattress changes the answer
On a soft mattress your shoulder sinks in, which shrinks the gap. On a firm mattress the shoulder stays up, so the gap is bigger. A rough adjustment:
| Mattress | Adjust your pillow height |
|---|---|
| Soft or plush | About 1–2 cm lower |
| Medium | No change |
| Firm | About 1 cm higher |
Typical heights by frame
| Build | Typical gap | Loft to look for |
|---|---|---|
| Narrow shoulders | 8–10 cm | Medium |
| Average shoulders | 10–12 cm | Medium to high |
| Broad shoulders | 12–15 cm | High |
| Very broad or muscular | 15 cm+ | Extra high, firm |
How to check your pillow tonight
Lie on your side on your current pillow and have someone take a photo from behind or above. Your nose, chin and breastbone should line up roughly with the middle of your spine. If your head tips down toward the mattress, the pillow is too low. If it tips up toward the ceiling, it's too high.
LoftFit gives general sizing guidance, not medical advice. If you have neck or shoulder pain that lasts more than a couple of weeks, numbness or tingling in your arms, or pain after an injury, see a doctor or physical therapist.