Mattress Guides

Mattress Dimensions Guide & FAQs

By The Mattress Nerd
mattress sizes

In the market for a new mattress? One of the most important choices you will have to make is which size mattress to purchase. There are several options available in the size department. If you’re feeling a little overwhelmed with trying to decide which size mattress to buy, don’t fret. We can help!

In this article, I will go over all the mattress size options available and discuss who each size might be a good fit for. In addition, I’ll also review the factors you should consider before selecting a particular mattress size. That way, you can decide where you fit on the spectrum and, at the very least, narrow down your options.

Standard Mattress Size Chart

Size Dimensions (in.) Dimensions (cm.)
Crib/Toddler 28” x 52” 71cm x 132cm
Twin 38” x 75” 96.5cm x 190.5cm
Twin XL 38” x 80” 96.5cm x 203.5cm
Full/Double 54” x 75” 137cm x 190.5cm
Full/Double XL 54” x 80” 137cm x 203.5cm
Queen 60” x 80” 152.5cm x 203.5cm
Olympic Queen 66” x 80” 167.5cm x 203.5cm
King (Eastern) 76” x 80” 193cm x 203.5cm
California King 72” x 84” 183cm x 213.5cm

Mattress Dimensions Guide

Crib/Toddler Bed Dimensions (28” x 52”)

Best Size For Infants & Toddlers

A crib or toddler mattress will measure 28 by 52 inches in size. This size mattress will be best for infants sleeping in a crib or toddlers moving from a crib to a toddler bed. In most cases, you can use the same mattress when moving from a crib to a toddler bed.

If the bed is meant to be for an infant, there are some key points you’ll want to keep in mind for safety. These mattresses are meant to last your child until they are about 18 months or 3 feet in height. It’s also best to search for an option that is as firm as possible. Very young infants can often roll onto their stomach and if the mattress is too soft, they are at a higher risk of SIDS or suffocation.  

Twin Bed Dimensions (38” x 75”) OR Twin XL (38” x 80”)

Best Size For Toddlers, Children, Single Adults

A twin size mattress will measure 38 by 75 inches. This is the smallest option available for adult sleepers. For taller individuals, you can often find a slightly longer twin mattress known as a Twin XL that will give you 5-6 more inches in length. Twin mattresses are best for toddlers moving into a traditional bed, as well as children and single sleepers.

Full/Double Bed Dimensions (54” x 75”) OR Full/Double XL (54” x 80”)

Best Size For Children, Single Adults, Couples, Single Sleepers w/ Child or Pet

A full-size mattress will measure 54 by 75 inches. It is also commonly referred to as a “Double Bed.” For taller individuals, you can often find a slightly longer twin mattress known as a Full or Double XL that will give you a bit more length. Full or Double mattresses are best for children, single adults with or without a child and/or pet and some couples. You should note, however, that a full-size mattress might be a bit cramped for two adults who plan to also sleep with their pet or child in bed.

Queen Bed Dimensions (60” x 80”) OR Olympic Queen (66” x 80”)

Best Size For Single Adults, Couples, Sleepers w/ Child or Pet

A queen size mattress will measure 60 by 80 inches. For taller individuals, you can often find a slightly longer option known as an Olympic Queen that will give you a bit more length. Queen mattresses are best for some single adults, couples, and sleepers with children or pets.

King Dimensions (76” x 80”) and California King (72” x 84”)

Best Size For Couples and Couples with Children and/or Pets

A king size mattress will measure 76 by 80 inches. For taller individuals, you can often find a slightly longer option known as California King that will give you a bit more length. However, keep in mind that these longer options are also a bit more narrow as well. King mattresses are best for couples with or without children and pets.

It’s worth noting that two twin mattresses make up the size of a king bed. So, if you’re planning for a king-size bed for you and your partner and you have very different sleeping preferences, you have the option to buy two separate twins.

Factors To Consider Before Choosing a Size

There are some factors you will want to consider before choosing a mattress size. For instance, who will be using the bed? Do you have any pets? Do you move a lot in your sleep? How big is your room? What is your budget? You might have a particular size in mind already, but ask yourself these questions before you make your final decision.

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

Be sure to factor in everyone who will be in bed with you. This includes not only a partner but also children and pets. If the number adds up, you might want to consider a larger mattress so you can accommodate everyone who wants to sleep in the bed.

Are you an active sleeper?

Have you been told you move around a lot in your sleep? Some people, even if they sleep well, tend to move frequently in their sleep. This can get a little tedious for your sleep partner night after night in cramped quarters. Even if the bed is just for you, you may need a bit of extra room if you find yourself going to sleep in one position or area of the bed and waking up in a totally different one in the morning.

What is your body type?

If you are a bigger person, either in size or height, you will definitely want to choose a mattress that can comfortably support your size. The worst thing you can do is buy a mattress that’s too small. It’s an important investment to make. Make sure it’s the right one for your body.

What are the dimensions of your bedroom?

This is a big one people often forget when they’re rushing into a mattress purchase. I suggest recording the dimensions of your room to make sure your new bed will fit in the room, along with your furniture and, that there is still room left to move around the room comfortably.

What is your budget?

We strongly suggest purchasing a quality mattress that will provide you with the rest and support you need to be at your best every day. If your budget is limited, it will definitely make a difference when choosing a size since a bigger mattress will undoubtedly cost you more.

So there you have it! While there are many different options available for your next mattress purchase, it’s important to take a moment to consider some factors before taking the leap on a new mattress.

Who will be sleeping in the bed? Are you an active sleeper? Do you need more space or length based on your size? How much space do you have to work within your bedroom? What is your budget for this purchase? Make sure to ask yourself these questions before you make your final selection.

Also, you should know that this guide is meant to give you an idea of what each size mattress can accommodate, but these guidelines aren’t meant to be rules. If you’re a single adult and would like the luxury of a king-size mattress, and your budget and room can accommodate one, go for it!

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Other FAQs

How much does a mattress cost?

Spend as much as is necessary to keep your body in proper alignment and minimize pressure on your body. In my mattress buying guide, I give some examples of what you get for each range.

Do I need a Boxspring?

Boxsprings these days, despite the name, rarely contain actual springs. Most are just rigid foundations. They exist to support the mattress. As long as you have a solid surface to support the mattress, you don’t need a boxspring. This means the floor is fine and most platform beds are fine. Old box springs that had actual springs in it are not fine. Neither is just a plain metal frame with one bar or a bed with 3 slats. As long as you have a platform bed with either a solid surface or enough slats that the mattress won’t be able to bend in between them, you can get away with not having a box spring.

Do I need a Bed Frame?

Like a box spring, a frame is there to support the mattress. You can put the boxspring and mattress directly on the floor, but that 1) doesn’t look nice, 2) isn’t as clean since you’re closer to the floor, and 3) eliminates any possible storage space under the bed. If you get a mattress a Full size or bigger, make sure the frame has a center support bar with at least one leg going from that bar to the ground.