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Three kinds of words show up on a pillow label. Some describe shape and size, some describe the fill and the fabric around it, and some name a certification. The last group causes the most confusion, because a certification usually covers one part of the pillow, not the whole thing.
Where a term comes from a standard or a certification program, the definition follows what that organization publishes. For a maker's own word, we say so, and you can read it as a claim, not a fact.
Shape and size
Shape and size
Size names describe the length of the shell. Height is a separate matter, and it changes once your head is on the pillow.
| Term | Meaning |
|---|---|
| Loft | The height a pillow holds, best judged under the weight of your head rather than at rest. Our loft guide covers how much each sleep position needs. |
| Gusset | A strip of fabric sewn between the top and bottom panels. It gives the pillow straight sides and a box shape, adds height and keeps fill from thinning out at the edges. |
| Baffle box | Inner fabric walls that divide a down pillow into chambers, so the fill stays spread out instead of drifting to one end. |
| Standard | The most common US pillow size, 20 x 26 inches nominal. |
| King | A long pillow, 20 x 36 inches nominal, sized so two span a king bed. Many people also stand one upright as a backrest. |
| Euro | A square pillow, 26 x 26 inches nominal, usually kept in a sham against the headboard. |
Fill
Down, fiber and foam
Fill decides how a pillow feels, how it holds height and how you can wash it. Our down and feather page goes further into the animal fills.
| Term | Meaning |
|---|---|
| Down cluster | The soft, quill-free plumage that grows under a duck's or goose's outer feathers. Under the US labeling standard explained by the testing lab IDFL, a pillow labeled simply "down" must contain at least 75% down clusters, and loose down fiber does not count toward that share. |
| Feather | Plumage with a quill. Feathers are flatter and firmer than down, and their quills can work through a thin shell. |
| Fill power | A measure of how much space a set weight of down takes up. Higher numbers mean loftier down. Fill power does not have to appear on the law label, and where a maker advertises it, the industry standard allows a 5% tolerance. |
| Down alternative | Synthetic fill, usually polyester fiber, made to imitate the softness of down. |
| Gel fiber | Polyester fiber treated with gel or blended with gel-coated fibers, usually sold as cooling. Read the cooling as the maker's claim. |
| Memory foam (viscoelastic foam) | Polyurethane foam that softens with warmth and pressure and recovers slowly, so it keeps the shape of your head for a moment after you move. |
| Shredded memory foam | Memory foam cut into small pieces and blown into a zippered shell, often mixed with fiber. The loose pieces let you change loft by adding or removing fill. |
| Cross-cut foam | A maker's name for shredded foam cut into small, even pieces, usually blended with fiber. It is a trade description, not a standard. |
| Latex | Foam made from rubber, either natural rubber from the sap of the rubber tree or synthetic. Allergists at the ACAAI advise people with a natural rubber latex allergy to avoid latex products. |
| Talalay latex | Latex foamed in a closed mold, expanded with a vacuum and flash-frozen before curing. The process gives a lighter, more even feel. |
| Dunlop latex | Latex poured into a mold and baked in one step. It tends to be denser and firmer than Talalay. |
| Phase-change material | A material that absorbs heat as it changes state, printed onto or woven into covers sold as cooling. How much it does for you is a maker's claim. |
| Off-gassing | The smell of new foam as it releases volatile organic compounds (VOCs). The EPA lists furnishings among indoor VOC sources and recommends ventilation, while noting that little is known about effects at levels usually found in homes. |
| Compression packing | Rolling or vacuum-sealing a pillow in plastic for shipping. A compressed pillow needs time out of the bag to regain its loft, and the maker usually says how long. |
Shell and cover
Fabrics, cases and covers
The shell is the fabric sewn around the fill, and the pillowcase goes over it. Weave and fiber change how a cover feels and how it washes.
| Term | Meaning |
|---|---|
| Thread count | The number of threads woven into a square inch of fabric. It is one of several things that shape the feel, along with the fiber and the weave. |
| Percale | A plain one-over, one-under weave that feels crisp and matte. |
| Sateen | A weave that floats more threads on the surface, giving a smooth hand and a soft sheen. |
| Lyocell (Tencel) | A fiber spun from dissolved wood pulp. Tencel is a brand name for lyocell. |
| Bamboo rayon (bamboo viscose) | Rayon made from bamboo pulp. The bamboo is dissolved and spun into a new fiber, so the fabric is rayon whatever the label stresses. |
| Encasement | A zippered cover that closes around the whole pillow. Allergists at the AAAAI advise encasing pillows in allergen-proof covers. |
| Pillow protector | A washable cover between pillow and pillowcase that catches sweat and skin oil before they reach the fill. |
| Sham | A decorative pillow cover, often with a flat fabric border, that usually opens at the back. |
Labels
Certifications and label claims
Each certification answers one narrow question about one part of the pillow. Our certifications page sets the main ones side by side.
| Term | Meaning |
|---|---|
| CertiPUR-US | A certification for the polyurethane foam inside a pillow, not for the pillow or the brand. Certified foam is tested for low VOC emissions (under 0.5 parts per million) and made without formaldehyde, heavy metals and listed flame retardants. Latex is outside the program. |
| OEKO-TEX STANDARD 100 | A label for textiles tested against the OEKO-TEX list of more than 1,000 harmful substances, with stricter limits the closer the fabric sits to skin. You can check any label number on the OEKO-TEX Label Check. |
| RDS (Responsible Down Standard) | A Textile Exchange standard for the welfare of ducks and geese: no live plucking, no force-feeding and an audited chain of custody. It says nothing about fill quality or allergies. |
| GOLS (Global Organic Latex Standard) | A Control Union standard for latex from certified organic plantations, with limits on harmful substances and emissions and traceability from plantation to retailer. In our reading, organic origin does nothing for someone with a latex allergy. |
| Hypoallergenic | A maker's word for a pillow meant to provoke fewer allergic reactions. None of the sources we cite defines it or sets a test for it, so we report it as the maker's claim. |
Questions
Questions buyers ask
Does a CertiPUR-US label mean your whole pillow is certified?
No. CertiPUR-US certifies the polyurethane foam inside, not the pillow, its cover or the brand. A latex core can't carry it at all, because latex is outside the program.
Is fill power the same as loft?
No. Fill power describes the down itself: how much space a set weight of it takes up. Loft is the height of the finished pillow, which also depends on how much down the maker puts in and how the shell is cut.
What does hypoallergenic mean on a pillow you're buying?
It is the maker's word for a pillow meant to cause fewer allergic reactions, and none of the sources we cite defines it. If dust mites are your concern, allergists at the AAAAI advise allergen-proof covers and washing bedding weekly at 130°F.
