In the United States, common bed sizes include Twin (39″ x 75″), Full or Double (54″ x 75″), Queen (60″ x 80″), King (76″ x 80″), and California King (72″ x 84″). The Twin size is often used for children’s rooms and small guest spaces, while the Queen size is popular for adults. The King and California King sizes provide the most space and are often used in master bedrooms. Check our bed size chart here.