What’s The Difference Between a Full Bed and a Twin XL Bed?

Full Bed

Twin XL vs Full: is there really a difference?  What if you just pick the one that’s available online or in-store? If you want to find the perfect mattress, you should not randomly choose one over the other. Both bed sizes have advantages and disadvantages. And these depend on several factors.

We’ll be talking about said factors shortly. And you’ll know by reading further what’s the difference between a Full bed and a Twin XL bed. Aside from the obvious difference in dimensions, other considerations can help you determine the right size for you. Contrary to popular notions, both Full and Twin XL are good for children and adults alike.

Dip into the Table of Contents to see the section you’re most curious about. But make sure to read through all of the points. We also prepared for you an entire section on things to know before you buy a mattress.

What Is A Twin XL Bed?

Twin XL Bed Dimensions

Next to Twin, Twin XL bed is 38 inches wide and 80 inches long (38 inches x 80 inches). Both share the same width, but the latter is 5 inches longer. This makes the Twin XL as long as the Queen. It features extra legroom for tall individuals. If put side by side, you can also use two Twin XLs to create a Split King mattress. 

Those who want to personalize the firmness on each side may opt for this style. You will need two Twin XL bed frames. Or you can just lay the two mattresses on a king-size foundation. Sheets for this size have to be customized, though. While these dimensions are pretty standard, you may still find it hard to source the appropriate bedding. You may use standard king sheets instead.

Who Is It For?

  • Little ones who are going through a growth spurt may suddenly find their small kid’s bed too small. While they’re not exactly ready for a Queen, they’ll probably appreciate extending their legs on an 80-inch long version. This is also less expensive than a big boy’s or big girl’s bed. Plus, it’s not going to make the bedroom look cramped, granted your child will stay in the same space.
  • College students living in dorms or apartments, where space is a luxury, can use this instead. A queen-size option seems too much. But a twin edition may feel uncomfortable for tall guys and gals. A Twin XL can still fit in narrow rooms, as well as bunk beds. Its price is ideal for college students, too. It’s an economical and practical choice.
  • Couples who want a split-type bed can place two Twin XLs side by side. They can lay each mattress on two separate foundations or use a King bed frame. Through this strategy, they’ll end up with a Split King mattress. It’s a simple solution for co-sleepers who want to customize the firmness of each side. For instance, one can get a Firm Twin XL while the other can pick Plush.

What Is A Full Bed?

Full Bed Dimensions

A full-size bed features 54 x 75 inches (width x length) of sleeping space. Also called standard double, this size is slightly shorter than a Twin XL. However, it is wider. A single adult who often shifts at night can snooze on this one. But a couple can also squeeze themselves in a double bed if space is limited.

Just consider a couple of things. One, two people will be using up 27 inches on either side of the mattress. So, obviously, a growing family may be hard-pressed to make room for a baby or a pet. Another thing, tall people may find themselves making do with the three inches’ worth of legroom. 

Who Is It For?

  • Growing kids who are being transitioned from the crib can enjoy the bigger space provided by the Full bed. It is wide but not long enough yet to feel strange. For parents, this choice is practical if they’re buying for the long-term. They don’t have to spend on a queen-size mattress, but they don’t have to be tied with a twin-size one.

Read: How to Transition from Crib to Toddler Bed

  • A double bed can also cater to college students or solo adults who sleep starfish-style. If you tend to be restless at night, you can toss and turn freely on 54 inches sleeping surface. And your dorm or apartment space won’t still feel cramped if you put it there.
  • Couples who don’t have kids or pets but are stuck in a small room should get a double bed. While a Queen version can fit, say, a one-bedroom unit, it can take up a lot of space. So this one is a more practical, if not less expensive, alternative.

Twin XL vs Full

It seems the nuances separate the Twin XL from the Full. But when it comes to target users, the benefits overlap. You can get either for your growing child or for yourself. It’s just a matter of checking your need for extra legroom or extra space for tossing and turning.

But let’s further look at the Twin XL vs Full conundrum.

While a Twin is a conventional choice for kids and adults, a Twin XL seems deliberate. That is, you’ll prefer it if you’re taller. It is also convenient for college students. But so is a full bed. Further, a Full or Double is often found in hotels. Two full-size beds are used in suites where the guests need to sleep separately. 

It should boil down to personal and space requirements. Consider the surface area of a twin-size mattress: 3,120 square inches. That looks good in longer but narrower layouts. A double-size bed covers 4,050 square inches. If the width of your room or apartment is wider, you can choose this.

Price is another determining factor. Twin XL costs less than Full. However, the former is non-conventional. You may find it harder to source bed sheets and/or a foundation to go with it.

Factors to Consider When Buying A Mattress

Construction & Materials

Design and components set the tone for the overall performance of a mattress. The external look should complement the quality of the materials inside. For all-foam and hybrid types, comfort and transition layers are usually made of memory foam, latex foam, or polyurethane foam. The base is composed of either high-density foam in all-foams or springs in hybrids.

Speaking of spring systems, individually encased coils/pocket coils or offset coils are found in modern ones. These are chosen over the more traditional Bonnell coils due to their durability, support, and breathability. For natural and organic claims, look for any of the following certifications:

  • CertiPUR-US
  • OEKO-TEX Standard 100
  • Global Organic Latex Standard (GOTS)
  • Global Organic Textile Standard (GOLS)
  • Rainforest Alliance
  • ecoInstitut

Firmness & Feel

The mattress industry uses the Standard Firmness Scale to help customers determine the feel of a model. You can choose Firm, Medium, or Soft based on a scale from 1 to 10. Depending on your sleeping position, a firmness rating will be provided as your match. Ultra-soft and ultra-firm, however, are not recommended to any sleeper type. Your weight is also a factor to consider:

  • Soft (3 to 4) – Those who weigh less than 130 pounds
  • Medium Firm (5 to 6) – Those who weigh 130 to 230 pounds
  • Firm (7 to 8) – Those who weigh above 230 pounds

In some cases, the manufacturer applies a reversed version of the firmness scale. You will find a score of 1 assigned as the firmest and 10 as the softest. The terms may also vary from one brand to another. For instance, plush can stand in for soft. This is not a hard-and-fast rule. It’s better to familiarize yourself with each company’s naming convention and scale.

Cooling/Temperature Neutrality

Cooling is a crucial factor for those who sleep hot. It can be produced by foam and cover with components that wick heat and moisture away. Gel, graphite, or copper is added to memory foam, allowing the quick absorption of heat through the material. Traditional memory foam is a popular heat trap. Changing up foam structure into open-cell also helps in facilitating airflow throughout the mattress.

Meanwhile, temperature neutrality also cools down your body while you sleep. At the same time, a bed with this feature warms you up during cold nights. It is also known as regulating temperature. And this is present in the phase change technology. Through this tech, foams, and covers can adapt to your skin temperature. 

Edge Support & Sinkage

What is edge support, and what is it for? Edge support is the function that holds you up if you tend to sleep on the side. It prevents you from experiencing the roll-off feel, or the feeling of falling toward the floor when you roll near the edge. You’d want a bed that offers stability instead. Often, poor performance in this area is determined through deep compression at the perimeter.

The lack of or minimal perimeter support can lead to significant sinkage over time. It can also cause sagging, which then results in an uneven sleeping surface. Compression, sinkage, and uneven sleeping surface are often signs you should replace your mattress.

Excellent edge support, then, enables the mattress to cover or extend its lifespan. Hybrids are your best bet in this department. Some but not all-foams may also work.

Motion Transfer

How about a motion transfer? This performance-related factor refers to the transfer of movements across the sleeping surface. Little to significant motion transfer may wake up sensitive sleepers, especially if their co-sleeper is restless. In other words, motion transfer can negatively affect your sleep quality. You should look for a mattress, whether it’s full or twin XL, that has good or better motion isolation.

Motion isolation keeps the movements within the area in which they were generated. Memory foam mattresses, as well as hybrids sporting pocket coils, are exceptional in this regard. Still, we suggest you check individual models to be sure they have what it takes to deliver.


If you’re buying a Full or Twin XL, you can find either size for any high-quality model. Such mattresses are available across different budget levels. To get an idea, here are the average price points or range for each mattress type. These are all for Queen, so expect lower prices for Twin XL or Full.

  • Innerspring – $100  to $2,500
  • Memory foam mattress – $500 to $1,500
  • Hybrid mattress – $1,600
  • Latex mattress – $2,000
  • Adjustable mattress – $1,000 to $3,500

If you cannot pay cash upfront, many brands offer financing programs through companies like Affirm and Klarna.

Other Factors

In finding the perfect fit, you must also factor in company policy on returns, exchanges, and warranties. Reading the fine print will help you avoid headaches later. While it’s safe to assume most online manufacturers offer free shipping and returns, double-check this on their website or in mattress reviews. These free services are often available to residents of the continental United States.

When it comes to sleep trials, the market average ranges from 90 to 120 nights. But some companies are generous enough to give you up to 365 days. Meanwhile, warranties can be valid for 10 to 25 years, depending on the manufacturer. There are a few that provide a lifetime warranty. But do take note that the average mattress lifespan is within 7 to 8 years.


Not only did you learn the differences between a Full bed and a Twin XL bed in this guide. You also reviewed the factors to consider before buying a new mattress. While it’s the dimensions that mainly differentiate the two sizes, minor details can also affect your decision. For instance, if you prefer a wider surface area, pick Full. Got long legs? A Twin XL would be good for stretching.

Your room, its space, and layout, also matter. If you have a narrow area, a twin XL-size bed is more practical. A full-size bed can work in a room where you need to maximize the width. Either way, you’ll have to measure your floor area. Lastly, you have to check out the price.

The sizes here are dependent on the pricing that is typical for a mattress type. Given all these factors, have you decided which one aligns with your needs yet?