The dimensions of a king-size pillow are 20 inches wide by 36 inches tall. Pillows can be stuffed with a variety of natural and synthetic materials, which are rated by their firmness and loft.
Natural fiber fills can include down and feathers, wool and cotton, while synthetic materials are usually polyester. The loft of a pillow refers to its height when it is flat on a bed. Low-loft pillows are thin, while high-loft styles are thicker. The firmness of a pillow, combined with its loft, should be matched to a user's sleeping style. Back sleepers do best with a medium-support pillow that cradles the head and spine. Side sleepers generally prefer pillows that support their heads and keep their spines in horizontal lines, while stomach sleepers usually want plump soft pillows.