A middle fill, for average side sleepers and people who switch positions
A middle fill means about 7 to 9 pounds of pure buckwheat hull in a standard 20 by 26 inch case, which sits below a full pillow.
In short: Run a 20 by 26 inch pillow at 7 to 9 pounds of pure hull, about 7 to 11 cm high, and adjust a handful at a time on your own bed.
The fill, specified
Every figure below comes from published seller specifications or pillow-height research, given as a range with its source. Nothing here was weighed or measured by this site.
| Item | Specification | Source |
|---|---|---|
| Target height, lying on it | 7 to 11 cm | A systematic review found moderate evidence for a 7 to 11 cm pillow height, as summarised in a later pillow-height study |
| Fill weight for a standard 20 by 26 inch pillow | 7 to 9 lb | A standard-sized pillow will require around 7-9 lbs of buckwheat hulls (Hullo guide) |
| Hull volume, in litres | The sources read give no litre figure. The seller's rate is about 200 cubic inches of hull per pound | The volume of buckwheat hulls is approximately 200 cubic inches per pound (Hullo fill calculator) |
| Polished or unpolished hulls | Either. Unpolished holds its shape firmly, and polished slides more quietly | Polished versus unpolished hulls |
| Pure hull or hull with wool | Pure hull, unless weight matters more to you than hold | What a buckwheat hull is |
Why your answers point here
If you landed here, the gap between your mattress and your head is middling. Side sleeping makes height the whole question. Average or narrow shoulders leave you a smaller gap than a broad frame does. A soft mattress shrinks that gap further as the shoulder sinks into it. A firm one keeps the body higher.
Some broad-shouldered readers land here for another reason. Full fills are heavier than they want. PineTales lists its 20 by 26 inch pillow at approx. 12–13 lbs, and its refill page says 10 pounds is enough to refill a standard-size 20 by 26 inch pillow. The middle band gives up some height for a lighter pillow. Pushing the hull into shape wins that height back.
Switching positions is the other way in. A fixed height suits you for only part of the night, so the fill needs slack. A case packed to the seams leaves the hulls nowhere to go. Too little fill fails the other way. The middle band leaves room for the hulls to move while the fabric still holds them. That slack lets a sleeper push hull under the neck when lying on the side and flatten it when lying on the back.
What moves the fill up or down
Your shoulder width drives height more than anything else. A lab study of side sleepers tested pillows at four height levels (8 cm, 10 cm, 12 cm, 14 cm) and worked out an individual height from each person's shoulder width. Too much height has a cost. In another lab study, the average cranial pressure at the 170 mm pillow was approximately 30% higher than at the 110 mm one. That is why narrow shoulders belong at the bottom of the weight range.
Add hull for a firmer mattress. Narrow shoulders call for less. Wanting a lighter pillow is also a reason to stay near 7 pounds, and the pillow weight guide explains what a lower fill costs in hold.
Sound does not change the fill. Hullo says the noise decreases over time as the hulls break in and their rough edges round off. If a crunch under your ear worries you, read the noise guide first.
What to check on your own bed
Lie on your side for a few minutes, with the pillow shaped the way you would sleep on it. Ask someone to look at your neck from behind. Nose, chin and breastbone should form one straight line. A head tipped toward the ceiling means too much hull. If the head drops toward the mattress, the pillow needs more. Change it by a handful at a time.
Then roll onto your back and check that pressing the pillow flatter brings your chin level. Hullo's calculator notes that most people prefer an "average thickness" between 3 and 4 inches, measured flattened, which is a sensible place to start before shaping. The height guide by sleep position goes through each position in more detail.