Full vs Full XL Mattress: Size Comparison + More

The main difference between a full vs full XL mattress is that full XL mattresses are 5 inches longer. Full mattresses measure 54" W × 75" L, while full XL mattresses measure 54" W × 80" L.

Here's a scenario that happens more often than you'd think: you're shopping for a new mattress, feeling confident about finally getting that sleep upgrade, when suddenly you spot "Full XL" next to the standard "Full" option. Wait—there's an XL version? Is your current mattress suddenly too small? Did you miss a memo?

Take a breath. You're not alone in this full vs full XL mattress confusion, and the answer is simpler than it seems. The key difference comes down to just 5 inches in length—that's it. But those 5 inches can matter depending on who's doing the sleeping.

This guide breaks down the dimensions, the differences, and most importantly, helps you figure out which mattress size actually makes sense for your sleep situation. No guesswork required.

Full vs Full XL Mattress: Quick Comparison

Need the facts fast? Here's what you're working with:

What Size Is a Full Mattress?

A full mattress measures 54 inches wide by 75 inches long. You might also hear it called a "double" mattress—same thing, different era. Back before the queen size became everyone's go-to, the full was the standard choice for couples. Times have changed, but the full hasn't lost its appeal.

With about 2,850 square inches of sleeping surface, a full fits comfortably in rooms as small as 10 feet by 10 feet—though a 10 by 12 setup gives you room to actually walk around your bed without performing gymnastics.

Who Should Sleep on a Full Mattress?

The full mattress hits a sweet spot for a lot of sleepers. Single adults of average height (under 6 feet) will find plenty of room to stretch out. It's also perfect for teens graduating from their twin beds—an upgrade that feels significant without overwhelming their space. Guest rooms love a full because it handles solo visitors and cozy couples alike without dominating the room.

Budget-conscious shoppers and apartment dwellers often land on the full for good reason: you get real sleeping space without the price tag or square footage demands of larger sizes. And for couples who genuinely enjoy sleeping close together? A full keeps things intimate while still giving you room to roll over.

Explore Casper's full mattress collection to find your perfect match.

What Size Is a Full XL Mattress?

A full XL mattress measures 54 inches wide by 80 inches long—the same width as a standard full, but with an extra 5 inches of length. That puts it on par with queen and king mattresses in the length department.

Here's the thing about full XL mattresses: they're not exactly everywhere. While the standard full is a fixture at every mattress store, the XL version occupies a much smaller corner of the market. Room requirements stay basically the same since the width hasn't changed—that extra 5 inches in length barely registers in most bedroom layouts.

Who Might Consider a Full XL Mattress?

The full XL targets a specific need: taller individuals (6 feet and above) who want more legroom but don't need—or don't have space for—extra width. It also makes sense for growing teenagers who might still be gaining height, and for anyone upgrading from a twin XL who wants to keep that same 80-inch length.

But here's a reality check: for taller sleepers who need that extra length, a queen mattress often makes more practical sense. You get the 80-inch length plus 6 more inches of width—and you won't have to hunt for specialty bedding.

Full vs Full XL: Key Differences Explained

Length Comparison

The full comes in at 75 inches long, which works for most adults. The full XL stretches to 80 inches, accommodating taller sleepers who'd otherwise be playing footsie with the end of their mattress.

A good rule of thumb: your mattress should be 10 to 12 inches longer than your height. For most people between 5'5" and 5'10", a standard full provides comfortable sleeping space with room to spare.

Width Comparison

Both sizes are 54 inches wide—no difference there. That width works well for single sleepers and provides a cozy fit for couples, giving each person about 27 inches of space. For comparison, a queen offers 60 inches of width, or 30 inches per person.

Here's something worth noting: if you're feeling cramped, width usually matters more than length. Most of us don't sleep in a perfectly straight line, so that side-to-side space tends to be more valuable than extra inches at your feet.

Price Differences

When you can find a full XL, expect to pay $50 to $150 more than the standard full, though the difference can vary by brand, materials, and quality. The limited selection also means less competitive pricing—fewer brands making them means fewer deals to be found. Full mattresses offer better value and significantly more options to choose from.

Bedding and Accessories Availability

This is where the practical differences really show up. Full sheets and accessories are everywhere—every store, every brand, every price point. Full XL bedding? That's specialty shopping territory. You'll likely end up ordering online, paying more, and having fewer options in colors and materials.

Setting up your bedroom is simply easier with a standard full size. Casper offers complete bedding solutions for full mattresses—sheets, pillows, and everything in between.

Full vs Full XL: Bedroom Space Requirements

Good news for room planners: both sizes fit similarly in bedrooms since they share the same width. A 10 by 10-foot room is the minimum for either, with 10 by 12 feet being ideal for comfortable movement and nightstand placement.

When you're measuring your space, think about walking paths, door swings, and closet access. Both full and full XL work beautifully in apartments, guest rooms, and smaller primary bedrooms. That 5-inch length difference? Basically negligible when you're laying out furniture.

The Full XL Availability Problem

Let's address the elephant in the bedroom: full XL is one of the least common mattress sizes on the market. Many respected mattress brands don't even offer it. That limited selection means fewer choices in comfort levels, materials, and price points.

The scarcity extends beyond the mattress itself. Bed frames, adjustable bases, and accessories designed for full XL dimensions require extra hunting. And if you're thinking about hand-me-downs or resale options down the road, full XL mattresses are rarely found on the secondhand market.

This isn't a dealbreaker for everyone, but it's definitely worth factoring into your decision.

Full vs Full XL: How to Choose the Right Mattress Size for You

Consider Your Height

Under 5'10"? A full mattress is an excellent choice—plenty of length with inches to spare. Between 5'10" and 6 feet? A full still works comfortably for most sleepers. Over 6 feet? Rather than hunting for a rare full XL, consider jumping to a queen, which gives you both extra length and extra width.

Think About Your Sleep Style

Back sleepers generally do well on a full—you're sleeping in a straight line, maximizing that 75-inch length. Side sleepers who curl up in a fetal position actually need less length, making a full ideal. Stomach sleepers? A full accommodates most of you comfortably. Restless sleepers who toss and turn might find that width matters more than length—if that's you, consider a queen for the extra side-to-side space.

Evaluate Your Bedroom Layout

Grab a tape measure before you commit. Account for dressers, desks, and that chair that always collects clothes. Check your door swing and closet access. A full fits more rooms comfortably than a queen while still offering ample sleep space—a solid middle ground for many bedroom layouts.

Factor In Practical Considerations

Think beyond today. Will you be moving apartments? Partners or pets joining you in bed? A full offers the most flexibility when it comes to bedding availability, bed frame options, and adapting to life changes. That practical versatility adds up over time.

Full vs Full XL vs Other Mattress Sizes

Understanding how full and full XL fit into the broader mattress size landscape helps put things in perspective:

Notice how the queen sits as the logical upgrade from a full for those needing more space—more width and the same 80-inch length as full XL, but with vastly better availability.

Final Verdict: Full or Full XL?

Here's the honest take: for most sleepers, a full mattress delivers the best combination of comfort, value, and convenience. It's widely available, reasonably priced, and you'll never struggle to find sheets that fit.

Full XL occupies a niche spot in the market—helpful for specific situations, but often not the most practical choice. If extra length is truly what you need, a queen typically makes more sense, giving you both additional length and width without the headache of hunting down specialty bedding.

Ready to find your perfect fit? Explore Casper's full mattress and queen mattress collections and try your next bed risk-free with our sleep trial. We've done the testing—hundreds of times—so you can just rest.

Why Choose Casper for Your Full Mattress?

We're serious about sleep (obsessed, really). Every Casper mattress is built with quality materials and construction designed for real rest—not just one good night, but years of them. Our sleep trial lets you test your mattress at home, in your own bedroom, with your own pillows. Free shipping takes the hassle out of delivery, and our warranty has your back long-term. Plus, with our complete bedding ecosystem of sheets, pillows, and bed frames, you can build a sleep setup that actually works together.

Frequently Asked Questions

Is full XL the same as queen?

No—and this is a common mix-up. A full XL measures 54 inches by 80 inches, while a queen is 60 inches by 80 inches. They share the same length, but the queen is 6 inches wider, offering noticeably more sleeping space. Queens are also much more widely available than full XL mattresses.

Why is full XL so hard to find?

Full XL is a niche size with limited demand. Most mattress brands focus their production on standard sizes—full, queen, and king—where the market is largest. For shoppers who need extra length, the queen has become the go-to choice, which has further reduced demand for full XL.

Is a full mattress big enough for two adults?

Yes, for couples who enjoy sleeping close together. A full provides about 27 inches of width per person—cozy, but workable. It's a solid choice for couples on a budget or in smaller spaces. That said, couples who want more personal space will likely prefer a queen.

What is another name for a full mattress?

You'll also hear it called a "double" mattress. The terms are completely interchangeable—same dimensions, same mattress. "Full" has become more common in recent years, but you'll find both names at any mattress retailer.

Can tall people sleep on a full mattress?

Most people up to 5'10" sleep comfortably on a full. Taller individuals may find their feet getting close to the edge, in which case a queen offers both extra length and width. Your sleep position also matters—side sleepers who curl up need less length than back sleepers who stretch out fully.

What size sheets fit a full mattress?

Standard full or double sheets, designed for a 54-inch by 75-inch mattress. These are widely available at all bedding retailers in every color, material, and price range. Casper offers full sheets designed to fit perfectly and stay put all night.