Current mattress models are manufactured in the following standard sizes: Crib, Twin, Full, Twin XL, Full XL, Queen, King, and California King. Most models are made in every size, though some of the smaller sizes are not. There are also “specialty” mattresses that are not conventional, such as the 33” mattress and the Wyoming and Alaska King, which are not available in the average mattress establishment.

Each of these mattress sizes is designed to meet a specific need, with factors like room size, how active a sleeper you are, your physical size, and whether or not you share the bed.

The crib mattress is a very important purchase because it’s where the majority of a child’s growth and development will occur. An infant will spend up to 70% of his or her time on the crib mattress and a toddler can spend up to 50% of his or her time on the crib mattress. Because a child will spend the first three to five years of his or her life sleeping and playing on this same crib mattress, purchasing a quality crib mattress is an extremely important decision. They need a firm, flat, even surface to maximize their development, both during sleep periods and when the infant begins to become more active in the crib, by pushing up, turning, and eventually, standing.

The twin mattress is the most common size for a single person. It is the perfect size for children, from toddler thru pre-teenage years. It is also the ideal size for a small guest room, or rooms in assisted living or health care facilities, which are normally quite small.

The twin extra long mattress is the common size in college dorms. It is 5″ longer than the twin, accommodating students of all heights. Twin XL’s are also used as pairs to accommodate couples who want individual control of their side of the bed with an adjustable base. This will allow each partner to raise and lower their mattress, as desired.

The full mattress is sometimes referred to as a “double” size. This was more popular for couples decades ago, when people were physically smaller. Now it is mostly regarded as a larger single bed. It is a nice step-up from a crib for a toddler if you read to your child in bed or she/he has sleep-over’s or sleeps with a pet. The full is also a nice option for a smaller guest room.

The queen mattress is the most common size for couples. In addition to a single box, it is available as a split box spring or split adjustable base. This is the option for spaces that may be difficult to deliver, such as an attic or basement bedroom, or a narrow stairwell with a low ceiling. The queen mattress is also available as a split mattress, as a specialty. This is an option for couples who disturb each other during sleep with motion transfer, and cannot fit a king size in the space. The queen split adjustable base, however, acts as a single unit — it is split for installation purposes only.

The king offers the most space of all the standard mattress options. The western and southwestern US refer to this as an “Eastern King” as opposed to the “California King” (described below). A split box is standard. For couples preferring to have independent flexibility, two twin XL mattresses are paired with two twin XL adjustable bases. Adjustable bases allow you to raise your feet and head, for reading, watching TV or working on your laptop. Two twin XL’s are the same size as a king.

The California King is 6″ narrower and 4″ longer than a standard king. This is a great option for very tall people, or a long narrow room. An adjustable base is not available for this size as of yet