Mattress Size Guide: Finding Your Goldilocks Bed

This one’s too big, and that one’s too small. How to find the mattress that’s just right.

As time passes and our lives change, so do sleep needs and habits. Finding a new mattress among the many different sizes is not always an easy process. Although mattress size is ultimately an individual preference, determining your sleep needs and understanding bed size dimensions will help lead you to the right choice.

There are some factors to consider when you begin to assess what mattress size you might need:

  • Do you sleep with a spouse or partner?
  • How large is the bedroom?
  • How tall is the person that needs the mattress?
  • Do pets or children share the bed?

When preparing your toolkit to shop for the right sized mattress, there is some research you might want to do beforehand. To be fully prepared, know the size of the mattress that you want to replace, the dimensions of the bedroom the mattress will go in, and any anticipated lifestyle changes. Having this knowledge as you begin your search will facilitate an easier buying process.

All set? We’ve summarized everything you need to know about sizing so you can feel confident you made the right choice for you and/or your family.


Crib: 28” x 52”

The standard size of all crib mattress, this is the number you should feel confident will match all standard crib sizes.

Don’t be surprised if you find these mattresses firmer than adult beds, they are manufactured that way for safety reasons. The timing for each child is different, but typically children will grow out of the crib at some point in the toddler-age range.

A crib mattress can be innerspring or foam. Some other qualities might be easy-to-clean and portability to keep up with all of the changes of childhood.

Twin: 38” x 75”

The smallest of the adult mattresses, the twin is a great choice for children transitioning from a crib or toddler bed, to an adult mattress.

The slim size of a twin makes it great for stacking as bunk beds, or or fitting them side-by-side in a shared bedroom. For smaller homes or apartments, or even guest bedrooms, the twin is a great size that will still leave you (hopefully) with some open floor space.

twin-xl-sizeTwin XL 38” x 80”

The twin XL has the same width of of a standard twin bed but with the added 5-6 inches of length. If you’re hoping to outfit your college student, Twin XL’s are the standard dormitory-sized bed. The added length gives a bit more room to a single-sleeping adult.

If hoping to extend the life of a mattress by having a bed transition from toddlerhood to the teenage years, choosing a twin XL from might save you money while ensuring your growing child will have all the space they might need. These mattresses are not only economical, but also maneuverable, and are easy to move from the bedroom, to the dorm room, or even to an apartment if circumstances allow.

Two Twin XL mattresses are also the standard split king mattress size.

An Important Note:

– not all sheet sets and comforters come in twin XL. Many bedding supply stores do carry the size nowadays, but it is something to keep in mind

Full: 54” x 75”full-size

A full-size mattress may also be referred to as a “standard double mattress.” A full-sized mattress is a great compromise between a twin and a queen size mattress. It’s great for a single sleeping adult who wants more room to sprawl, or for a couple with a smaller bedroom.

The additional space is loved by growing teens, and is an economical and popular option for young adults as they transition into their first, and typically smaller, apartments. For parents that choose a full size mattress for their child, it is a great mattress to utilize for a guest bedroom when grown children eventually move out.  

The mattress is shorter than a queen or king, so it is good for a sleeper or couple who does not require a lot of legroom. A couple sleeping in a full-size mattress with children or pets is possible, but it may be a tight squeeze.

An important note:

-For a single sleeper, that is 54” of sleep space (14” extra compared to a Twin or Twin XL)

-If a sleeper is 6’ tall, there is only 3” of additional space when the sleeper is fully extended

-For a couple, that is 27” of sleep space per person (about 11” less than a Twin or Twin XL)

queen-sizeQueen: 60” x 80”

The most popular mattress size in the country, the queen is provides a comfortable sleep experience for a wide range of people. Whether a single sleeper or a couple, a Queen mattress size is one that won’t be outgrown. A Queen can give some more room for those that share a bed with children or pets, as well.

Most bedrooms can easily accommodate a queen size mattress, but to be safe it’s recommended that your bedroom measures at least 10’ x 10.’ Because of its popularity and size, purchasing bedroom accessories and bedding is a bit more economical than those for a king bed.

An important note:

-For a single sleeper, that is almost double the amount of sleeping space compared to a Twin/TwinXL

-A 6’ tall sleeper would have 8” extra sleep space if fully extended on a Queen

-For couples, that is 30” of sleep space per person (8” less than a Twin size mattress)

Some specs to consider:

For single sleepers, that is 60” of sleeping space.

For partners, that is 30” of sleeping space per person (8” less than a Twin size mattress).

A 6’ tall sleeper would have 8” of extra space if fully extended on this mattress.

king-sizeKing: 76” x 80”

A King size mattress provides generous extra space for a single sleeper or partners. If your feet have ever hung off the end of a mattress, a California King is the only mattress that will give you that extra length you’re looking for. For those that share a bed with children or pets, this extra sleep space will provide a more comfortable sleep.

Check to be safe that your room dimensions are at least 12’ x 12’ to ensure that a King mattress will fit. For those that have the budget and bedroom space, we would recommend this size over a Queen for couples, especially those sleeping with children and pets.

A King size mattress is equivalent to two Twin XL’s pushed together. For partners looking for an adjustable base, or with very different sleep preferences and habits, split king mattresses allow you to customize your ideal sleep surface.

An Important Note:

-For couples, the sleep space per person is equivalent to a Twin or Twin XL

-A 6’ tall person would have 8” of sleep space when fully extended on a King (which is the same length as a Queen)

-Split King sheet set bundles exist, but can be more difficult to find than standard sizes

california-king-sizeCalifornia King: 72” x 84”

4 inches longer but 4 inches narrower than a standard king type. Good for taller individuals.

A California King mattress is ideal for taller individuals or those that want a mattress with extra length. It is 4” longer than a standard King mattress, but it is also 4” narrower. Even though a few inches narrow than a standard King, it is still generous in sleep space for single sleepers, couples, and couples who sleep with children or pets.

The bedroom dimensions for a California King are the same as a standard King–12’ x 12.’

An important note:

-For couples, there is 2” less of sleep space per person compared to a Twin size

-A 6’ tall sleeper has an entire 1 foot of extra sleep space when fully extended on a California King

Still not sure which mattress size will be the right one for you? Find a mattress that has a generous sleep trial so that you can actually see how well it fits in the bedroom. By having multiple nights to sleep on the mattress, you can get a better feel if the mattress size is provides you will sufficient sleep space. But a word from the wise: we’ve never heard  someone complain that their mattress is too big!

wyoming-king-sizeWyoming King: 84″ x 84″

A Wyoming King is great for those who want just a little bit of extra space rather than the surplus that an Alaskan King might provide. A Wyoming King is a great choice for those who sleep with small children, and fewer or smaller pets.

It’s essentially the happy-medium of ginormous mattresses. Like the Alaskan King bed, the Wyoming King bed is typically a custom order. Using the 12-16 comforter rule, you would want a comforter that is approximately 96” length and 100” width.

alaskan-king-sizeAlaskan King: 108″ x 108″

An Alaskan King bed can be found pre-made by some mattress retailers, but chances are you will not find one in the big-box mattress stores. The best route to go for ordering an Alaskan King bed is a custom order.

If you are going to splurge on a mattress of that size, you might as well custom order it to be exactly to your liking. Many manufactures are willing to work with you so that your covers, foam thickness and densities, and technology is perfected to your desires. This way, you will know exactly what is going into your mattress.

Custom ordering will give you a higher quality mattress, and might not be as expensive as you may think. Learn more about custom mattresses.