A California King mattress is a large mattress size designed for those who need extra length. It measures 72 inches wide by 84 inches long, making it ideal for taller individuals who want more legroom while sleeping. This size is popular among couples who prefer spacious sleeping arrangements. The California King is narrower than a standard King mattress, which measures 76 inches wide by 80 inches long. This unique dimension allows it to fit better in narrower bedrooms while still providing ample space for two sleepers. Many bedding retailers offer a variety of options for California King mattresses, including memory foam and innerspring models.