Shopping for a mattress can get a little confusing with all of the different sizes available. Aside from standard twin, twin long, double, full and queen beds, there are two types of king size mattresses that each have two different names. The difference between an Eastern king size mattress and a California King size mattress is that the California king is 4 inches (10.2 cm) longer and 4 inches (10.2 cm) narrower.
Eastern King
The Eastern king size mattress, also known as a standard king, is the widest mattress that is commonly available. At 76 inches (193 cm) wide and 80 inches (203.2 cm) long, it is the mattress of choice for many large adults or couples who want a lot of room for spreading out in their beds. It is 18 inches (45.7 cm) wider than a queen bed and allows each person 38 inches (96.5 cm) of room — about the same amount of room that pushing two twin beds together would provide. An Eastern king size mattress typically comes with two twin box springs that fit side-by-side for easy transportation.
California King
The California king size mattress, also called a Western king, is the longest mattress that is commonly available. At 84 inches (213.4 cm) long, it is 4 inches (10.2 cm) longer than the Eastern king and is preferred by many people who are more than 6 feet (1.8 m) tall. Like an Eastern king, it typically comes with two twin box springs. For some people, the drawback of this mattress is that, at 72 inches (182.9 cm) wide, it is 4 inches (10.2 cm) more narrow than the Eastern king.
A Matter of Preference
People who want a king size mattress for its length more than its width often choose the California king. If the extra length is not required, such as for people who are shorter, the accommodating width of an Eastern king size mattress is often preferred. To get the length of a California king and the width of an Eastern king, a custom-made mattress is likely to be needed.
Sheet Shopping
The difference between an Eastern king and a California king can be a factor when a person is shopping for a set of bed sheets. Someone who knows that he or she needs king size sheets but doesn't know whether the bed is an Eastern king or California king — or doesn't even know that there are two types of king size mattresses — could end up with sheets that are too short and wide or too long and narrow. If the type of king size mattress is not specified on its label, it might be necessary for its owner to measure the mattress before shopping for sheets.