Mattress Sizes & What Size Room You Should Have Them In

You would not believe how many mattress sizes there are. Honestly, I was unsure of how many there were until I started doing a little bit of digging. Sure, you have your standard sizes, but did you know that there are also custom and extra long? I didn’t either. It came to my attention that a lot of people just pick a size because it seems like the right idea, but it may not be. You can’t pick one that doesn’t fit in your bedroom and you can’t pick one too small if your partner enjoys their personal sleeping space. Check out these mattress sizes and what they are best suited for.

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#1. Crib

This one is kind of obvious, but the standard crib mattresses are specifically designed for babies and cribs. A full size crib mattress should be 28 ⅝ inches wide by 52 ⅝ inches in length and no more than 6” thick. Sizes will vary, but as long as they are close to those dimensions and fit your specific crib without being too small or too thick, it’s okay. Once your baby outgrows the crib, these mattress sizes will also fit most toddler beds.

Recommended room size would be similar to the size recommended for a twin bed, which is 7’ x 10’.

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#2. Twin

A twin is a very common size in most children’s bedrooms. They are small and leave enough room for their toys and other belongings. The standard measurements for twin beds are 39 x 74 inches. A twin bed is also best for dorm rooms, apartments, and those who sleep alone or with a small animal, such as a cat. There isn’t much room for movement, but it gets the job done in terms of just sleeping and relaxing.

Twin beds are also most commonly used for bunk beds, but you can also find them in combinations such as twin over full or twin over queen if there are multiple sleepers on the bottom or for those who have outgrown the twin size but share a smaller room with someone.

The twin bed is a wonderful solution for couples who are looking to share a room, but not a bed. In 2015, the National Sleep Foundation found that nearly 25% of couples sleep in separate beds. It’s ideal for couples who need their own sleeping space, it helps them sleep better, there are no disruptions from movement, and some couples are just much happier.

The recommended room size for this bed is 7’ x 10’ or 10’ x 10’ for two twin beds in the same room.

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#3. Short Twin

The short twin is very commonly found in motor homes. Since motorhomes and campers are much smaller than your home, everything is going to be smaller, such as the beds. These short twins are usually 34 x 75 inches, giving you 5 inches less length and 1 inch more in width. You may also be able to get these for the home as well in a custom size.

The recommended room size for this bed would be 7’ x 10’.

#4. Twin XL

The Twin XL is for those who need extra leg room, such as a taller individual or someone who tends to move down the bed while they are sleeping. These measure 39 x 80 inches, giving you an extra 6” in length. It also gives your pet some room at the foot of the bed.

The recommended room size for this bed would be 7’ x 10’.

#5. Full

The full mattress can also be called a “double bed” and are very commonly found in hotel rooms. These are 16 inches wider than a twin, measuring in at 54 x 74 inches. They have the ability to sleep two smaller individuals comfortably, although, if you’re a frequent mover in your sleep, your partner may not appreciate the size of the bed.

These are ideal for older children who are outgrowing the twin bed. This size also allows parents to cuddle up next to their children while they are tucking them in for the night. These are also a very common size for a futon, which is a couch that folds down into a bed. If it’s not large enough, you can opt for a queen size futon, which is just a tad larger.

The recommended room size for this bed would be 10’ x 12’.

#6. Full XL

The Full XL is another size that gives you more foot room. It measures 54 x 80 inches, giving you an extra 6 inches. These are great for tall individuals who need the extra foot room, but don’t need or want the extra width that they would get with a queen bed. These are also nice for those who have partners who like to cuddle and don’t care about needing personal space while they sleep.

The recommended room size for this bed would be 10’ x 12’ – 10’ x 16’ depending on how much walking room you want.

#7. Standard Queen

Standard Queen beds are the most common size bed in the world. They are big enough to accommodate two sleepers comfortably, giving each one optimal room to move around and reposition while giving you the opportunity to be close enough for cuddling. It measures 60 x 80 inches, giving single sleepers more than enough room for movement or having kids and pets sleep with them occasionally.

They are much larger than the other beds, meaning you need to have adequate space in your bedroom to fit it in. They are ideal for guest rooms and teenagers room as well. If you are a single sleeper in a queen bed, you won’t have a problem finding enough room to fit your desired sleeping position, especially if you are a frequent mover.

The recommended room size for this bed would be anywhere from 10’ x 10’ – 10’ x 14’ depending on how much walking room you want.

#8. Olympic Queen

The Olympic Queen bed measures 80 x 66 inches, giving you an added 6 inches of foot room. These are perfect for taller individuals who still need the width, but aren’t quite interested in upgrading to the King size. These fit great in rooms that are longer than they are wide. If you have a dog that loves to lay on the end of the bed, this will accommodate them very nicely.

The recommended room size for this bed would be anywhere from 10’ x 10’ – 10’ x 14’ depending on how much walking room you want.

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#9. California Queen

Coming in at 84 x 60 inches, the California Queen is perfect for couples who need the extra space for movement, but don’t need the added foot space. Couples do occasionally like their personal space while they are in bed, and the four extra inches of width on this bed will give you just that. It also gives more room for the child that loves to cuddle up next to their parents if they wake up in the middle of the night.

The recommended room size for this bed would be 12’ x 10’ – 12’ x 14’ depending on the amount of walking room you want.

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#10. Standard King

The King bed is perfect for couples who like a maximum amount of sleeping space, while giving them more than enough space for other activities such as relaxing in a comfortable, stretched out position. It measures 76 x 80 inches, making it almost as large as two twin XL beds put together. It’s also the ideal size for homes with larger rooms or for those who frequently expect a child or a pet to share the bed.

If you sleep alone on this massive bed, you’ll have plenty of space to lay in any position you want for sleeping, relaxing, or pain relief. You can lay sideways to read a book or watch television. Honestly, the possibilities are endless. Also, the box springs for these mattresses are split, making it much easier for them to be maneuvered around, especially through stairwells and tight corners.

The recommended room size for this bed would be 10’ x 12’ – 13’ x 13’ depending on how much walking room you want.

#11. California King

The California King bed is one of the longest sizes you can possibly get, unless you have a mattress custom made for you. It measures 72 x 84 inches and is the ideal bed for those who need more length than width. It’s 4 inches narrower than the standard king, but you gain 4 inches in length. It’s still 6 inches wider than a queen, giving you and your partner more than enough room to sleep or cuddle, your choice.

It’s ideal for adjustable beds because of the way adjusting the elevation effects the bed. The California King bed is what I sleep on, and it gives my husband and myself optimal room for just about anything, plus our kids and dog who occasionally invade the bed. Honestly, there’s enough room for a third person to sleep.

The recommended room size for this bed would be 12’ x 12’ – 14’ x 12’ depending on how much walking room you want.

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There certainly quite a few different mattress sizes on this list, a few of which I did not know existed. Each person has their own individual preference as to what size they want, how much sleeping room they need, what kind of space they have to work with, etc. Before you choose the size, make sure it will fit, your partner agrees with it, and it’s best for your individual sleeping habits.

Photo credit: Leremy/Shutterstock

Frequently Asked Questions

Will king size sheets fit a California king mattress?

The main difference in size between a California king and a standard king mattress is in the width and length. A king mattress is 76 inches by 80 inches, and a California king is 72 inches by 84 inches. The best option is to find a king size flat sheet that measures the largest dimensions of both king and California king, making them 102 inches by 108 inches. At that size, the sheets would be interchangeable between the king and California king.

Should a mattress be the same size as a bed frame?

This is an important question to consider when deciding what size mattress will fit into a specific space. Generally speaking, the dimensions of a bed frame should roughly match the mattress size, but the bed frame may have a few inches added to the width and length due to the construction and design of the bed frame or to make space for bedding. Aside from making sure the bed frame will fit into the room, it is important to make sure the base of it fits the mattress. For example, a queen-size mattress should be placed on a queen bed frame. If the bed frame is too big, there will be gaps on the side of the mattress, and if it’s too small, the mattress may bend, bunch up or fold, which could cause sagging or damage the mattress.

Should a box spring be the same size as a mattress?

A box spring, which differs from a platform base, is a bed base or mattress foundation that has a wooden frame and either actual springs or metal rods that provide support to a mattress. The box spring is usually the same size as the mattress that sits on it. However, sometimes with queen and king size mattresses, instead of one large box spring to support the mattress, often two smaller box springs are used and attached underneath so they stay in place. This is done when a home or apartment has narrow hallways or an elevator. While the king or queen mattress is malleable and can be bent or folded, that size box spring cannot, and may not fit around a corner or in the elevator. That’s when two smaller ones make sense.

What size mattress will fit on a cot?

If you are thinking of using a cot in your RV or for when guests sleep over, while the actual dimensions of the cot must be taken into consideration, using a narrow twin size mattress is probably your best bet for a child or an adult sleeping on the cot.