Most pillow advice stops at your sleep position. Side sleepers high, back sleepers medium, stomach sleepers low. That is the right starting point, but it skips the second half of the equation: your body. Two side sleepers can need very different pillow heights, and here is why.
Shoulder width is the hidden variable
When you lie on your side, the gap your pillow has to fill is basically the width of your shoulder. Broad shoulders create a bigger gap, so you need more loft to keep your head level. Narrow shoulders need less. This is why a pillow that is perfect for your partner can leave your neck aching, even if you both sleep on your side.
A simple starting chart
Use your sleep position for the base height, then nudge it with your frame:
- Side sleeper, broad or tall frame: aim for the high end, 5 to 6 inches or more.
- Side sleeper, average frame: 4 to 5 inches.
- Side sleeper, smaller frame: around 4 inches.
- Back sleeper, larger frame: 3.5 to 4 inches.
- Back sleeper, smaller frame: 3 inches.
- Stomach sleeper, any frame: under 3 inches, as flat as comfortable.
Your mattress changes the math too
A soft mattress lets your shoulder sink in, which shrinks the gap and means you need a little less loft. A firm mattress holds your shoulder up, opening the gap, so you need more. This is why the same pillow feels different when you change beds.
Why a chart can only get you close
A chart narrows the range, but it cannot account for your exact shoulder, your exact mattress, and how you shift at night. That last inch of fit is the difference between a decent night and waking up genuinely rested. The honest fix is a pillow you can adjust. Start at the height your body size suggests, then add or remove shredded fill until your neck sits in a straight line with your spine. Every Dreamy Blue pillow ships overfilled so you can tune to your number instead of rounding to the nearest size on a shelf.