TOG rating

TOG is a unit originally developed to measure the thermal insulation of textiles, and it is now the standard way duvets and some blankets are labeled for warmth. A higher TOG number means more insulation and a warmer duvet, while a lower TOG number means a lighter, cooler one.

For hot sleepers, checking TOG rating is one of the more reliable shortcuts when shopping for a duvet insert, since it is a standardized number rather than a marketing description. Summer-weight duvets are typically rated at the low end of the scale, while winter duvets sit much higher, and some brands offer a mid-range option meant to work across seasons.

The mistake to avoid is picking a duvet by fill material alone without checking its TOG rating, since two duvets with the same fill type can still carry very different warmth ratings depending on fill weight and construction. Matching TOG rating to typical bedroom temperature, rather than season alone, gives a more accurate result for someone who runs warm.