Compared

Each comparison here names its basis before its verdict, and every figure links to the page it came from.

Is wool or down warmer?

Down, for its weight. A wool comforter reaches the same warmth by carrying more fiber, so it lies heavier on the body.

A duvet insulation study cites lab work finding that down's thermal resistance is significantly higher than wool's at the same filling weight (ScienceDirect). Fill weights show the gap: one mill fills its wool queen with 4 pounds of wool (Frankenmuth Woolen Mill), while a down maker's queen for fairly warm bedrooms holds 25 ounces (Cuddledown).

Which handles sweat better?

Wool takes water vapor into the fiber, so the air against the skin stays drier, but most head-to-head figures come from the wool trade.

Tests commissioned by British Wool at Bangor University reported faster moisture transmission through wool duvets than through feather and down ones (British Wool). The sleep evidence is thinner. A lab trial found no effect of wool against polyester bedding on sleep (Nature and Science of Sleep), and a review found the one significant duvet result was for goose down against cotton in a cold room (Journal of Sleep Research).

Which is easier to care for?

Neither by default. Care follows the product, and some comforters of each fill are machine washable while many are not.

Among down comforters, some are dry clean only (Egyptian Linens). Among wool ones, untreated fills felt in a machine and washable fills use treated wool. Our full comparison, wool vs down comforter, sets out warmth, sweat, allergies and care for your own room.