Mattress Sizes and Dimensions

Finding the Right Mattress Size

Choosing the right mattress size isn’t as straightforward as it might seem. While it might be tempting to simply buy a twin-size for your children and a queen for you and your spouse to share, there are lots of other factors that come into play. 

For example, how much space can your bedroom accommodate? What type of bed-frame will you use, and does it require any specialty sizing? If you sleep alone, do you want a snug fit or space to stretch out? If you sleep with a partner, do they toss and turn enough that you need a larger surface area for motion isolation? 

This guide will walk you through everything you need to know to choose the right size mattress. We’ll go over standard mattress sizes and the people they’re best for, dimensions to consider beyond length and width, and a checklist of things to consider before making your final choice.

Standard Mattress Sizes



Dimensions Height Accommodation Number of Sleepers
39″ x 75″ 5′ 9″ 1

Twin-sized beds are an ideal fit for the bedrooms of children and most adolescents of below-average and average height. In general, they can last most children until adulthood, when they’re ready to size up to a full or even a queen-sized mattress. Due to the height accommodation limit of twin mattresses, adolescents of above-average height should consider choosing twin XL mattresses instead. 

Twin XL


Dimensions Height Accommodation Number of Sleepers
39″ x 80″  6′ 1″ 1

Often referred to as “dorm mattresses,” twin XL mattresses are capable of accommodating most average-sized adults and adolescents of above-average height. Typically, they’re suited to college dorms and adult bedrooms that happen to be short on space. That said, if your child wants more room to stretch out and has a bedroom with enough space, they’re perfectly suitable for children, as well.  



Dimensions Height Accommodation Number of Sleepers
54″ x 75″ 5′ 9″ 1

Also known as double beds, full-sized mattresses are an excellent choice for adults who sleep alone and don’t require that much room. They’re also a great fit for teen bedrooms, guest bedrooms, and bedrooms for working professionals in high-density metropolitan areas who might be short on space. 



Dimensions Height Accommodation Number of Sleepers
60″ x 80″ 6′ 1″ 2

For adults who sleep alone and can afford a little more space, queen-sized mattresses are a popular choice. At 60 x 80 inches, they provide plenty of room for single sleepers to stretch out, and can also accommodate couples who share a bed and don’t mind sleeping close to their partners.  



Dimensions Height Accommodation Number of Sleepers
76″ x 80″ 6′ 1″ 2

 Unless you really want a lot of extra room, king-sized mattresses are generally too big for single, below-average and average-weight adults. Instead, they’re most suitable for couples who want extra wiggle room and/or move around a lot in their sleep. 

California King


Dimensions Height Accommodation Number of Sleepers
72″ x 84″ 6′ 6″ 2

For sleepers who find the height accommodation of a king-sized mattress to be too cramped, they should find a suitable alternative by sizing up to a California king. This happens to be the largest standard size available on the market and generally costs the same as a king-sized mattress. Because they’re taller and narrower than king mattresses, California kings may not be suitable for single sleepers who need more surface area due to weight requirements or couples who need more room than a king.



Dimensions Height Accommodation Number of Sleepers
28″ x 52″ 3′ 9″ 1

These mattresses are meant to be used exclusively in cribs and should never be used without a frame. Made extremely firm to meet safety standards, they’re best for babies and young toddlers (2-3 years old) who still sleep in cribs, and can be used either in nurseries or parents’ bedrooms if space allows. Due to safety issues, they should not be used by toddlers who are too big to be sleeping in cribs or who are mobile enough to crawl out by themselves.



Dimensions Height Accommodation Number of Sleepers
28″ x 52″ 3′ 9″ 1

These mattresses are meant to be used exclusively in toddler beds and, like crib mattresses, should never be used without a frame. Far softer than crib mattresses, they’re best for toddlers and small children who have yet to outgrow toddler-sized beds. In general, toddler mattresses are an optional transitional step between cribs and regular beds. Once your toddler outgrows his or her crib, it’s safe to size up to a twin-sized mattress. 

Mattress Thickness and Weight

When it comes to sizing your mattress correctly, there’s a lot more to consider than just length and width. Depending on the type of bed-frame you have and your personal needs and preferences, the thickness/height and weight of your mattress will both make a huge difference. 


The typical thickness or height of a standard-size mattress ranges from 8 to 13 inches. The thickness you’ll require will depend largely on the bed frame and sheets you have, as well as your weight requirements. Most bed frames have a maximum thickness they can accommodate, and the vast majority of fitted sheets won’t stretch over mattresses past a certain height. Thickness can also affect the sag, support, and comfort of a mattress. Thin mattresses can leave heavier sleepers feeling like they’re sinking or otherwise unsupported, and these folks may want to search for thicker mattresses. On the other end of the spectrum, mattresses that are too thick for lighter sleepers can make them feel like they’re floating or sleeping on top of their comfort layer. 


The weight of a mattress depends mostly on its material. Foam and latex mattresses tend to weigh the least, while innerspring mattresses and innerspring hybrids typically sit on the heavier end of the scale. As with thinner mattresses, lighter mattresses may not provide enough support for heavier sleepers, while heavier mattresses may be too firm and unyielding to be comfortable for lighter sleepers.

How to Choose the Right Mattress Size

Aside from the surface area, thickness, and weight of your mattress, you’ll also want to think about your personal requirements. How many people and/or pets will be sleeping on the mattress? How big is your room? Are you fine with sleeping closely to your bed-mates or do you like your personal space? These are all factors that should be taken into consideration before settling on the size of your mattress.

Number of Sleepers

Will you be sleeping alone or with your partner? Do your pets share your bed? Do your kids climb in with you? In general, mattresses smaller than a queen are unsuitable for more than one sleeper. Depending on the size of your pet, however, even a twin may be big enough to comfortably fit a person and a furry friend. 

Body Type

Your body size and weight will dictate the size of mattress that’s safest for you to use. While a mattress may be able to support a sleeper’s weight, it may not have enough surface area to comfortably accommodate their body. On the other hand, a mattress with plenty of surface area may not be able to safely bolster a sleeper’s weight. Before choosing your mattress, make sure you research the weight limit of your mattress.


Are you a combination sleeper who tends to move around and switch positions during your sleep? Then you may want to opt for a wider mattress. Do your children or pets often share you and your partner’s bed? A king-sized mattress may be your best bet. The amount of personal space you need can be the difference between a queen and a California king. 

Room Size

Even after taking into account the above considerations, you’ll want to take out a tape measure and make sure your bedroom can accommodate the mattress size you choose. Consider factors like how much space you want between the bed and other pieces of furniture, whether the bed will be pushed against a wall or remain free-standing in the middle of the room, whether you want room for a decorative headboard, and whether you’ll be able to comfortably sit up on your mattress without hitting your head. 


The sleeper’s age is most important for mattress sizes smaller than a queen. This is both for comfort and safety reasons. For example, toddlers who are old enough to crawl out of cribs should size up to toddler beds, while babies and young toddlers should not be sleeping in twin-sized mattresses or anything bigger. On the other end of the spectrum, most adults will likely find twin-sized mattresses to be too cramped for their tastes, while full-sized mattress may be too roomy for adolescents.