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Guides

The reference pages. Sizes, firmness, materials — the facts, without a product attached.

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The pages with nothing to sell

These are the reference pages. No picks, no buy buttons, no commission — just the facts you need before a product page is any use to you. They exist because most of the confusion in this category isn't about which mattress to buy; it's about vocabulary that's been deliberately muddied.

Start with sizes if you're buying a frame or a room

Mattress sizes is the plainest page here: every standard US size in inches, in a table, with the two things people actually get wrong. First, a King and a California King are not big-and-bigger — a King is wider (76 inches) and a Cal King is longer(84 inches). If you're tall you want the Cal King; if you share the bed with a sprawler you want the King. Second, a Twin XL is the same width as a Twin but four inches longer, which is why two of them side by side make a split king.

Sizes also decide what will physically fit together, which is the other reason people land here with a tape measure in hand. The commonest version of that question is whether an adjustable base can go inside a bed frame you already own — usually it can, once the slats or box spring come out and the base stands on its own legs, but it turns on four measurements and on a leg-height spec that almost no product listing publishes.

Then firmness, because the scale is fiction

The firmness guide exists to explain that the 1–10 firmness scale everyone quotes has no standards body behind it. It is a marketing convention. One brand's 6 is another's 7, and there is no referee.

Worse — and this is the bit that actually costs people money — firmness isn't a fixed property of the mattress at all. It's a relationship between the mattress and your body. The same bed reads firmer to a lighter person and softer to a heavier one, because weight is what compresses foam. So "medium-firm" on a spec sheet is not a promise; it's a hint about what the manufacturer was aiming at. That single fact explains most of the one-star reviews in this industry.

The same page separates firmness from support, which get used interchangeably and are completely different things. Firmness is how the surface feels. Support is whether your spine stays in line. A mattress can be very firm and support you badly.

Materials: the two comparisons that decide most purchases

Memory foam vs hybrid is the mattress fork. Foam contours and isolates movement; hybrid breathes and supports the edges. If you sleep hot, the coil core wins and no amount of cooling-gel marketing changes it — foam insulates because that's what foam is.

Percale vs sateen is the bedding fork, and it catches people out because both are usually cotton. The difference is the weave, not the fiber. Percale is a plain grid: crisp, matte, breathable. Sateen floats threads across the surface: silky, lustrous, warmer. Hot sleepers want percale. Thread count is largely a distraction in both cases.

Why these pages have no products on them

Because they'd be worse if they did. The moment a reference page has a buy button on it, every sentence in it becomes suspect — you'd be right to wonder whether we're explaining fill power or steering you.

These pages do link to our roundups, and we do earn a commission if you buy from those. That's the deal, stated plainly: here's how the site is funded and here's what we won't do for money. If a guide here ever reads like an advert for a specific product, we've failed and you should email us about it.

Recently added

Four that fill real gaps. Baffle box vs sewn through is the comforter construction question that decides whether your duvet has cold lines across it; what GSM means covers the one number that actually predicts how warm a flannel or linen sheet will be; flannel vs fleece sheets explains why one of them feels warmer and the other sleeps warmer; and why is my down comforter flat will probably save you the price of a replacement.

What's missing

Deliberately: anything medical. No sleep apnea, no insomnia, no CPAP, no supplements. Those are health questions with real consequences, and the sites that cover them properly retain actual doctors to review the copy. We don't have one, so we stay out of it rather than improvising. More on where we draw the lines.