Mattress Sizes and Dimensions

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When it comes to mattresses, comfort is crucial. But that’s not the only thing to consider when buying a new bed. Size, for example, is an important feature to focus on.

Keep reading for a rundown of the best mattresses for single adults, couples, teenagers, kids, toddlers, and babies. We even have details on the best mattress sizes for RVs, campers, and air mattresses!

Unsure of what size you need? Check out our video below to find out!

Standard Mattress Size Chart

Here’s a helpful chart to help you visualize how big each type of mattress is.

SizeDimensions (in.)Dimensions (cm.)
Crib/Toddler28” x 52”71cm x 132cm
Twin38” x 75”96.5cm x 190.5cm
Twin XL38” x 80”96.5cm x 203.5cm
Full/Double54” x 75”137cm x 190.5cm
Full/Double XL54” x 80”137cm x 203.5cm
Queen60” x 80”152.5cm x 203.5cm
Olympic Queen66” x 80”167.5cm x 203.5cm
King76” x 80”193cm x 203.5cm
California King72” x 84”183cm x 213.5cm
Mattress Sizes
Mattress Sizes

Crib/Toddler Bed Dimensions 

  • Dimensions: 28” x 52”
  • Best bed size for: Infants and toddlers

The standard dimensions for a baby or toddler mattress are about 28 inches wide by 52 inches long. These mattresses are ideal for infants and toddlers who sleep in cribs.

When your child transitions from a crib into a toddler bed, you should be able to use the same mattress. Most children can sleep comfortably on this type of mattress until they’re 18 months old or 3 feet tall.

Babies and toddlers should sleep on a very firm surface. Studies show that firmer mattresses reduce the risk of Sudden Infant Death Syndrome (SIDS), while softer mattresses can increase the risk of suffocation.

Twin Bed Dimensions  

  • Dimensions: 38” x 75” or 38” by 80”
  • Best bed size for: Children, teens, or single adults

The standard size of a Twin mattress is 38 inches wide by 75 inches long. Twin mattresses are best for children and teens, but adults may find these beds comfortable, too. They’re also good for toddlers who have transitioned into larger beds.

Adults might be more comfortable sleeping on a Twin XL mattress. They have the same width but give you five extra inches of length. They’re usually found in college dorms.

Full/Double Bed Dimensions (54” x 75”)

  • Dimensions: 54” x 75” or 54” by 80”
  • Best bed size for: Children, single adults, couples, or people who share their bed with pets

Full mattresses are 54 inches wide by 75 inches long. You can also get a full XL bed, which is 54 inches wide by 80 inches long.

Also known as double mattresses, full mattresses are designed to accommodate children and single adults best. However, they can also work for some couples or single folks who sleep with pets in the bed.

Queen Bed Dimensions

  • Dimensions: 60” x 80” or 66” x 80”
  • Best bed size for: Single adults, couples, or people who share their bed with pets

Queen-size mattresses are 60 inches wide by 80 inches long. Or, you can opt for an Olympic Queen, which is 66 inches wide by 80 inches long.

Queen mattresses are an excellent option for teens, single adults, or people who sleep with their pets. Couples may also like Queen mattresses, depending on how much personal space you prefer.

King Dimensions

  • Dimensions: 76” x 80”
  • Best bed size for: Couples, families, taller people, or larger people

Standard King-size mattresses are 76 inches wide and 80 inches long. They work well for taller people or anyone who wants room to stretch out. They’re also ideal for couples who don’t want to disturb one another when they toss and turn.

California King 

  • Dimensions: 72” x 84”
  • Best bed size for: Couples, families, taller people, or larger people

California King mattresses have the reputation of being gigantic. But in reality, they’re four inches narrower than traditional King mattresses and only four inches longer. That said, they often serve the same purpose as regular Kings. However, they might be ideal for tall sleepers or if you have pets who sleep at the foot of your bed.

RV Camper Mattresses

  • Dimensions: 28” to 35” x 75” to 79”
  • Best bed size for: RV or campers

While you can probably get away with using a traditional mattress in an RV or camper, you might be better off getting a mattress designed for sleeping on the road.

RV mattresses range from 28 inches to 35 inches wide by 75 inches to 79 inches long. You can find more lightweight options than standard mattresses, making them easier to move.

RV Mattress Size Chart

Here’s a helpful size chart to help you pick the right mattress dimensions for your RV or camper.

RV Mattress SizeDimensions (in.)
RV King72” x 80”
RV Queen60” x 80”
RV Short Queen60” x 75”
RV Full/Double53” x 75”
RV Three Quarter48” x 75”
RV Bunk28 to 35” x 75” to 80”
RV Truck35 to 42” x 79” to 80”
RV Twin28” x 75” to 80”

Air mattresses 

  • Dimensions: 38” to 76” x 75” to 84”
  • Best bed size for: children, single adults, or couples

Air mattresses are great if you have guests sleeping over, or if you want a comfortable place to sleep when you’re camping. They’re also helpful if you need a mattress in the interim, either when moving or waiting to buy a traditional mattress.

Air mattresses come in a wide range of sizes. You can find them in the same dimensions as Twin, Twin XL, Full, Double, Queen, King, or California King mattresses.

The Best Mattress Size for Couples

Here’s a rundown of the best mattress size for couples.


Queen mattresses can accommodate most adult couples. However, they might not be big enough if you also share your bed with pets or children.


King mattresses offer an ideal width x length ratio, making them a fabulous fit for couples. The downside is that they might be too large for certain spaces and are often more expensive than smaller options.

Still unsure on which to pick? Check out more about Queen vs King mattresses.

California King

California King mattresses are longer (but narrower) than regular King mattresses. This makes them ideal if you or your partner(s) are taller. But, they might not be best if you want more width or if you share your bed with a partner and children.

Check out all the differences in a California King vs a regular King.

The Best Mattress Size for Single People

Single people rejoice! You can find comfort in a wide variety of mattress sizes. Plus, you don’t have to worry about buying a bed that suits a partner’s comfort needs.


Full-size mattresses are a great option for children, teens, and adults alike. They’re more compact than Queen beds, so they’re easier to fit in smaller spaces. But if you’re taller or have a larger body mass than average, they might not provide enough space for your comfort.


Queen mattresses offer the best of both worlds. They’re larger than Full beds, but take up a lot less room than Kings. They also provide an excellent width x length ratio for single sleepers, so you have plenty of room to stretch out and roll around.

If you’re tall, you may prefer an Olympic Queen which offers a bit more length. 

Still thinking? Check out our pros and cons for Full vs Queen size mattresses.


King-size mattresses can accommodate almost anyone, regardless of body size or height. However, they take up a lot of room and might be too big for children who sleep alone.

The Best Mattress Size for Children

Kids deserve a great mattress, too! Here are the best-sized mattresses for children. 


A Full mattress provides an adequate amount of length and width for most children. But they might be too small for taller teens. They’re also compact, so they should fit in smaller bedrooms. 


Twin mattresses are ideal for kids who are going from toddler beds to larger beds. They’re narrow, making them a good fit for smaller rooms or bunk beds.

To help with your choice, check out our article on Twin mattresses vs Full mattresses.

Twin XL

Twin XL mattresses are a good option for teens or kids who are still getting taller. But they might be a bit too big for young children just transitioning into larger beds.

Check out our article on Twin vs Twin XL mattresses if you’re struggling to pick between the two.

Factors To Consider Before Choosing a Size

Not sure what size bed you should get? Here are some important factors to keep in mind.

How many people (or pets) will be in bed?

Consider how many people (or pets) will be sleeping in the bed each night. If you and your partner like to spread out, you may want to opt for a Queen. And if you have kids that like to crawl into bed, a King might be even better.

Are you an active sleeper?

If you toss and turn or roll around a lot, you may want a larger bed. This reduces the risk of falling off the bed in the middle of the night. Plus, if you share a bed with someone, you’ll be less likely to disturb their sleep if there’s extra room. 

What is your body type?

You might be more comfortable in a larger mattress if you’re tall or if you have an above-average body mass.

What are the dimensions of your bedroom?

Be sure to measure the size of the bedroom before you buy a new bed. This will help you determine the ideal mattress for your space.

What is your budget?

You can find a high-quality mattress at almost any price point. But, generally, larger beds are more expensive than smaller beds.

Mattress Sizing FAQs

Can two people share a Full-size bed?

Yes, but some people might not be comfortable sharing a 54-inch wide bed with someone else every night. According to our study, people that have a King-size mattress are the most satisfied sleepers.

What is a California King mattress?

A California King mattress is longer but narrower than a standard King-size mattress. A California King is 72 inches wide by 84 inches long while a normal King is 76 inches wide by 8- inches long. They’re ideal for taller individuals, or for those who have pets who sleep on the foot of the bed.

Is there a difference between Twin XL and Full-size mattresses?

A Twin XL mattress measures 38 inches wide and 80 inches long, and a Full bed mattress measures 54 inches wide and 75 inches long. For taller, thinner teenagers and young adults who will be sleeping alone, a Twin XL can provide a comfortable sleep experience. For larger teenagers or young adult couples, a Full-size mattress may be the better option.

What’s the most popular mattress size?

Queen mattresses – which are 60 inches wide by 80 inches long – are the most common mattress size. They’re arguably the most versatile mattress for adults and can be used for single sleepers, couples, and people who share their bed with pets or kids.

Is there a difference between Twin and Single mattresses?

A single-size mattress measures 30 inches wide by 75 inches long, while a twin mattress is 38 inches wide by 75 inches long. Twin mattresses are better suited for larger children who need extra room and personal space while they sleep.

What are standard mattress sizes?

Here’s an overview of the most common standard mattress sizes in the United States:

  • Crib/toddler: 28” x 52”
  • Twin: 38” x 75”
  • Twin XL: 38” x 80”
  • Full/Double: 54” x 75”
  • Full/Double XL: 54” x 80”
  • Queen: 60” x 80”
  • Olympic Queen: 66” x 80”
  • King: 76” x 80”
  • California King: 72” x 84”

You can also get an air mattress that ranges from 38” to 76” x 75” to 84”, or an RV/camper mattress, which ranges from 28” to 35” x 75” to 79”.


When buying a bed, deciding on a mattress size is an important first step. From there, you can consider other important factors like cost and comfort. 

Generally, a Queen mattress is the most versatile bed for single sleeper adults and couples alike. But, they might be a bit too big for kids who would probably be more comfortable on a Twin, Twin XL, or double/full bed. 

You may also prefer a King or California King mattress if you like extra space when you sleep, or if you sleep in the same bed as a partner. 

Just be sure to measure your room before you pull the trigger on a new mattress. While a big bed can be great, it might not suit your suite.

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