A comforter is a type of blanket that keeps the use warm and can also serve as a mattress pad. Sizes generally correspond with bed sizes, such as full down comforters for queen/full sized beds. These comforters are slightly larger than the actual size of the bed to allow draping on the sides. Duvet, or down covers provide protection for prolonged use of the comforter.

Comforters are filled with layers of different kinds of materials, such as down feathers, wool, or silk. It is usually stitched to secure the filling and keep it evenly distributed. The shell or covering is usually made from cotton, silk or polyester fabrics, with varying thread counts which measures the warmth of the comforter. Comforter shells vary in design, usually to match with other beddings.