California King vs. Full: What’s the Difference?

By Geoff McKinnen
Last Updated On June 29th, 2020

The California king is the longest of all standard size mattresses, while the full mattress is one of the shortest. The Cal king beds are popular among couples and tall…

California King vs. Full: What’s the Difference?

The California king is the longest of all standard size mattresses, while the full mattress is one of the shortest. The Cal king beds are popular among couples and tall people, while full mattresses are good for average size single sleepers.

In this article, we discuss the main differences between these two standard sizes and help you choose the perfect size mattress for yourself.

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What is a California King Size Mattress?

A California king mattress measures 72 inches by 84 inches. It is 4 inches longer and 4 inches narrower than a regular king, which is also called the Eastern king. The extra-long Cal king size bed is an ideal choice for tall people.

Since the Cal king bed was first manufactured by a Los Angeles mattress merchant, the name of the state is associated with this bed size. A Cal king is also called the Western king because it originated on the west coast.

A Cal king bed has ample space for a couple and can comfortably accommodate children if they want to sleep with their parents on some nights. Compared to a full, these big Cal king beds are expensive. The average price of a Cal king mattress is $1500, but you’ll find mattresses priced higher or lower than this because the price depends on the quality of the materials used to make the mattress.

Full vs California King

A California king bed is also available in a split Cal king version. A split Cal king mattress is a regular Cal king size split in half, allowing each sleeper to choose different firmness levels on their side of the bed. The split versions work well with adjustable bases too, as they let you elevate your head and feet according to your preference without bothering your partner.


  • Spacious enough for couples, can fit children as well
  • An excellent option for tall sleepers
  • Available in split versions, allowing comfort customization for both sleepers


  • Doesn’t fit in smaller rooms
  • Expensive

What is a Full Size Mattress?

A full size mattress measures 54 inches by 75 inches and is popularly called the double bed. Though called the double bed, it doesn’t have ample room for two adults to sleep comfortably. At most, it can accommodate an adult and a child.

Before the introduction of the queen, king, and Cal king beds, full beds were popular among couples, so they got the name “double beds.” Up until the 1940s, Americans were mainly sleeping on twin and full size mattresses. A twin was used as a single bed, while the full served as a double bed.

In the late 1940s, the country witnessed an economic boom, enhancing the buying power of Americans. The American people needed larger sized beds to furnish their big bedrooms in huge houses. Later, in the 1950s, the average height and weight of Americans were increasing, adding to the demand for bigger beds.

With so many larger sized mattresses available on the market, the full size is now used by single sleepers who don’t have enough space in their room. Full size mattresses are common in guest rooms, smaller bedrooms, or studios, where space is limited. On average, a full size mattress costs $1000, but the price depends on the quality of the materials.

Sometimes, full beds are used in the children’s rooms because they can easily accommodate two children. They are often used on the lower bunk in some bunk beds. Bunk beds optimize space, leaving more room for children to play.


  • A smart option for those with limited space
  • Available as bunk beds


  • Not long enough for tall people to sleep comfortably
  • Can’t accommodate two adults

Size Comparison of California King and Full Size Mattresses

A California king bed is 18 inches wider and 9 inches longer than a full bed, making it a good choice for couples. A full bed doesn’t provide adequate space for a couple, but it is a good option for single sleepers who don’t have the budget or space for a queen bed in their room.

ParametersCalifornia kingFull
Mattress Dimensions (IN)72 inches by 84 inches54 inches by 75 inches
Mattress Dimensions (CMs)182.88 cm by 213.36 cm137.16 cm by 190.5 cm
Recommended Room Size (FT)12 feet by 12 feet10 feet by 10 feet
Recommended Room Size (CM)365.76 cm by 365.76 cm304.8 cm by 304.8 cm
Common inBig master bedroomsGuest rooms, children’s rooms, and studios
Suitable forCouples and tall sleepersSingle adults and children

Other Standard Sizes

If the California king or the full size does not suit your sleep needs, there are other popular mattress sizes available online or in mattress stores. When buying a mattress, factor in the space taken up by other essential bedroom furniture such as lamps, nightstands, and a dresser.

Ideally, leaving 2 to 3 feet of space on all three sides (except the side against the wall) of your bed makes your room look neat. This set-up also leaves you with sufficient walking space. Following are the other standard mattress sizes:

Twin Size Mattress

Dimensions: 38 inches by 75 inches

A twin size mattress is 16 inches narrower than a full so they don’t need as much room space. This compact size mattress can even fit in a room measuring 7 feet by 10 feet, but its short length cannot accommodate tall sleepers. A twin is the same length as a full bed.

A twin bed is a good option in a child’s room. A child usually graduates from a crib to a twin bed. Families with more than one child often use bunk beds available in twin and twin XL sizes.

Twin XL Size Mattress

Dimensions: 38 inches by 80 inches

A twin XL size mattress is 5 inches longer than a twin and full, making it a better choice for taller people. The extra length comes in handy to accommodate growing teenagers as well. Twin XL beds are common in children’s rooms, college dorm rooms, and shared bedrooms.

Queen Size Mattress

Dimensions: 60 inches by 80 inches

A queen size bed is 6 inches wider and 5 inches longer than a full. It’s the ideal option for single sleepers because it allows sufficient space to stretch out while sleeping. The queen bed is also used as a couple bed, allowing each sleeper 30 inches by 80 inches of space. Though a queen is not as spacious as a Cal king bed, it’s the right size for couples who don’t have large bedrooms for bigger beds.

King Size Mattress

Dimensions: 76 inches by 80 inches

A king size mattress is the widest of all standard size mattresses. It is 4 inches wider but 4 inches shorter than a Cal king. A king bed is the perfect size for couples and it has enough room for small children as well.

Like Cal king beds, even standard king size mattresses are also available in split options. Since a twin XL mattress is the exact half of a king bed,  placing two twin XL mattresses side by side makes a split king mattress.


Which is a better option: a king or California king?

Both king and Cal king size beds have plenty of room for a couple, but a Cal king is 4 inches longer than the king. If you or your spouse need some extra legroom, a Cal king is a good option. Otherwise, a king size mattress is better because it is 4 inches wider than a California king size bed. If children want to sleep with parents some nights, then a king will be more spacious than a Cal king. Plus, the total surface area of a standard king is more than a Cal king bed.

Do two twin XL beds make a California king bed?

No, two twin XL beds placed side by side makes a king bed. A twin XL mattress is the exact half of a king bed, so placing two of them together makes a king, but a Cal king has different dimensions. A Cal king bed is narrower and longer than a king, so two twin XL mattresses will not add up to the size of a Cal king bed.

Do king size sheets fit a California king bed?

No, king sheets will not fit a Cal king bed. A standard king bed measures 76 inches by 80 inches, while a Cal king bed is 4 inches longer and narrower. A fitted sheet meant for a king bed will be too short and wide for a Cal king mattress. Cal king sheets are readily available online or in bedding stores. A Cal king is a standard mattress size, so finding compatible bedding accessories is not difficult.

Is a full size bed good for couples?

No, a full size does not have adequate space for a couple. It can fit an adult and a child but will be too small for two adults. In fact, some couples feel cramped even in a queen, which is 6 inches wider than a full bed.

Is a full size bed the same as a queen?

No, a full size bed is 6 inches narrower and 5 inches shorter than a queen. A full mattress is a good option for single sleepers who don’t have sufficient space for a queen, while a queen size mattress can be used by both single sleepers and couples. Though a queen bed is not the best option for couples, it’s the right fit in small master bedrooms.


The Cal king and the full cater to different sleeper needs. While the Cal king is always the best option for tall sleepers because no one likes to sleep with their feet dangling out of the bed, the full size mattress is good for average size single sleepers. Finding the right size mattress for yourself is crucial to a good night’s sleep. If you don’t get enough space to stretch out and relax your muscles while sleeping, your sleep quality gets affected and poor sleep causes daytime drowsiness, impairing productivity.

This article is for informational purposes and should not replace advice from your doctor or other medical professional.

About the author

Geoff McKinnen is a writer focusing mainly on the healthcare industry and has written articles on everything from foods to help you lose weight to the connection between Alzheimer’s and sleep. Geoff’s passionate about helping readers improve their well-being to lead happier lives. Outside of work, Geoff enjoys cycling and hiking and believes that by leading a healthy lifestyle, he can help others do the same.

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