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twin xl vs full mattress dimensions illustration

Twin XL vs. Full: What’s the Difference?

Whether you’re looking for the best mattress for your teenager or you’re trying to figure out which mattress size will fit best in your small apartment, you’ve got a few good options to choose from. Both the twin XL and full size mattresses are great choices for teens—or solo-sleeping adults.

What’s the difference between a twin XL and full—and which one is right for you? Our twin XL vs. full size mattress guide will help you determine just that.

Twin XL mattress size

As its name suggests, a twin XL is an extra-long twin size mattress. A twin XL mattress measures 38 inches wide by 80 inches long, making it a full 5 inches longer than a standard twin.

Pros of a twin XL

A twin XL mattress has many benefits. Here are the biggest reasons to choose this mattress size:

  • Twin XL beds are great for teens. Since teens often experience growth spurts, the added length of the mattress will be helpful. Measuring 80 inches long (roughly 6 feet 7 inches), this is a particularly good option if you believe your teen will be over 6 feet tall. If you’re a taller adult who has a small bedroom, you may also benefit from choosing a twin XL mattress.
  • Twin XL dimensions make for a nice fit in dorm rooms—especially for tall college students. “Twin XLs are ideal for college students because they provide more length, which is great for kids who study in bed or want to hang out with friends on their bed,” notes Prudence Bailey, founder and principal designer of Prudence Home + Design in Connecticut.
  • If you and your partner have different sleep needs, you can put two twin XL mattresses together to make a split king. For example, if you like a firm mattress but your partner prefers a soft mattress, consider a split king so each of you has a separate sleep surface with your preferred mattress firmness.

Our Best Split King Mattress for Couples





Solaire Precision Adjustable Air


Featuring 50 precise firmness settings on each side of the bed for personal customization. Talalay latex and gel-infused memory foam layers provide luxury comfort and support.


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Cons of a twin XL

While a twin XL has plenty of pros, there are a few cons to consider as well.

  • It’s too small for two. Given that a twin XL mattress is only 38 inches in width total, it doesn’t afford much space for two people. A queen size bed, which measures 60 x 80 inches, is the ideal mattress size for couples because each sleeper gets about 30 inches of space to themselves.
  • It can be a challenge to find bedding that fits since a twin XL mattress is less common than a standard twin. However, don’t try to fit full size sheets onto a twin XL bed. A full size bed is 5 inches shorter and 16 inches wider than a twin XL, meaning full size sheets won’t fit properly. (Here’s what you need to know about special mattress sizes before you buy one.)
  • You’ll pay more for a twin XL than you would a standard twin. “Twin XL beds are a bit more expensive than regular twins,” says Bailey. Plus, not all mattress retailers stock twin XLs regularly, she adds.
twin xl vs full - full dimensions illustration

Full size mattress

A full size mattress (also known as a double bed) measures 54 inches wide by 75 inches long.

Pros of a full

Just like a twin XL, a full size mattress has quite a few things going for it. Weigh these benefits before you buy:

  • Full size beds offer an ideal situation for solo sleepers. If you live by yourself, a full size bed will provide ample room.
  • This mattress size is a natural fit in downsized spaces. Those who live in apartments or who have small bedrooms will find that a full size bed is a good option. A full size bed can fit comfortably into a bedroom that’s at minimum 10 feet by 10 feet.
  • Full size beds are a great option for children. Bailey speaks from her first-hand design experience, saying, “We use full size beds a lot when designing kids’ rooms since it’s a bed that they won’t outgrow until they leave home.”
  • They’re also usually less expensive than their larger counterparts and easier to transport than bigger mattresses.

Our Best Full Size Mattress for Children





Saatva Youth


This dual-sided innerspring mattress provides optimal support and comfort to children of all ages. Simply flip it over from the 3+ side to the 8+ side when your child is ready.


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Cons of a full

Keep these drawbacks in mind before shopping for a full size mattress:

  • They don’t provide adequate space for most couples. In a full size bed, each person will only have 27 inches of space for themselves. “Size is the biggest downside, as most adults will find it too small to share,” says Bailey. That said, if you’re not physically large and don’t mind snuggling, it could be just fine. “If they are a cuddling couple, this is the size for them,” says Bailey.
  • Since they’re not especially long, full size beds aren’t a great option for tall folks. A full size bed is just barely over 6 feet in length, so you’re looking at feet hanging over the edge of the bed if you’re a few inches over 6 feet tall. Taller individuals will be better suited to a twin XL, queen, or if you have the space, king size mattress.

These Saatva Mattresses Come in Twin XL and Full Sizes




Saatva Classic


Our flagship luxury mattress is expertly engineered with coil-on-coil construction for durability, a layer of memory foam for enhanced back support, and a cushiony Euro pillow top for extra comfort.


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Loom & Leaf Memory Foam


Premium memory foam, handcrafted in the U.S. with eco-friendly materials. Breathable organic cotton, cooling spinal gel, and layers of high-density support foam assure a cool, comfortable night’s sleep.


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Zenhaven Latex Mattress


100% Talalay latex responds to every curve for pressure-free support and responsive comfort. Talalay latex is supple, resilient, and durable, for the ultimate in elevated sleep. (It’s naturally hypoallergenic too.)


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Is a twin XL or full right for you?

We’ve put together this handy comparison chart to help make your choice between a twin XL vs. full easier.

ComparisonTwin XLFull
Width38″54″
Length80″75″
Min. recommended room size7′ x 10′10′ x 10′
Who it’s best forTall children, teens, or adults

Couples (when you pair two twin XLs to make a split king)
Children and teens

Solo sleepers who want a little more room to move around
DrawbacksMore expensive than a standard twin

Can be hard to find bedding
Not enough room for couples

Not long enough for anyone over 6 feet tall

Still not sure which mattress size is right for you? Check out our mattress dimensions guide for helpful advice.