Memory foam pillows typically come in the following sizes, although the exact dimensions may vary by manufacturer:
Standard (20” x 26”): Standard pillows are the smallest and most commonly used size, and can be used on any size bed.
Super Standard (20” x 28”): Super standard pillows are relatively rare. With a length halfway between the size of a standard and a queen pillow, they may be suitable for any mattress up to a queen.
Queen (20” x 30”): Queen size pillows are commonly available as an alternative to standard pillows. They give a little more playing room to people who move around during the night, or who like to sleep with their pillow folded or scrunched up.
King (20” x 36”): In addition to providing plenty of room while sleeping, king pillows are also one of the most comfortable sizes to lean against while sitting up in bed. Most online bedding companies offer king size pillows.
Body Pillow (54” x 20” OR 48” x 20”): Body pillows are long and skinny, meant to be cuddled against. These are most frequently used by side sleepers, who tuck them between the legs to keep the hips aligned and reduce strain on the lumbar area. Body pillows may also be an invaluable sleep tool for pregnant women, and can be a comfortable backrest when sitting.