Bed Dimensions And Mattress Types 101 — Everything You Ever Needed To Know

In theory, a bed is a very simple thing — it's a rectangle of padding or springs that cushions your body while you sleep. But when buying your dream bed becomes a reality, there are tons of terms to understand and factors to consider. For example, what size mattress is right for you and your bedroom dimensions? What the heck is a hybrid, and can it help minimize back pain? Which mattresses work best with an adjustable bed base so you can sleep like an astronaut? Once you're actually in the thick of it, the shopping process can start to get a little overwhelming. That's why we've compiled all the information you'll need in order to find the perfect mattress — and you won't have to deal with lines, showrooms, or pushy salespeople. Phew! 

First thing's first: Who is the mattress for, and how old is that person? Typically, you start with a small single as a newborn or toddler, graduate to a twin as a kid, maybe sleep on a twin XL in college, and end up with a full, a queen, or a king as an adult. Most mattresses are marketed in terms of age because they coincide with the size of one's body — but preferred textures and firmness levels also differ depending on how old you are.

For example, the best mattress for a small child will fit inside a crib or toddler bed, but it'll also be firm and breathable for safety reasons. A mattress for a teenager, on the other hand, will usually be a bit softer, but should also account for sudden growth spurts. If you're a senior citizen, your bed should conform to your body to support your spine, hips, and neck — otherwise, you'll wake up with aches and pains. When buying a mattress for a couple, you have to ensure that the firmness level suits both preferences and that it's big enough that no one's waking up with an elbow in their face. Extra points if it doesn't squeak. 

Unfortunately, though, the size of your mattress isn't always about what you want — it's also about what'll fit comfortably in your bedroom. Do yourself a favor and measure the size of your room before you start shopping. Nothing's worse than falling in love with your dream bedroom set only to find that it would stretch from wall to wall. According to interior designers, the ideal room will contain 60 percent furniture, 30 percent walking space, and 10 percent decorative items. Luckily, most mattresses and bed frames are available in multiple sizes, but some are definitely harder to find (like twin XL or California king). If you narrow it down from the start, you can find what you're looking for without hassle and without disappointment. After that, you're well on your way to the best night's sleep possible.

Common Mattress Sizes And Bed Dimensions

As we previously mentioned, the size of your mattress is important for two reasons: It has to fit your body (or bodies), and it has to fit inside your bedroom without taking up every last square foot. Before you dive in, you should note that European bed sizes are different from standard mattress sizes in the US and Canada — so if you're shopping internationally, it's a whole different ball-game that probably involves centimeters. 

These are the most common mattress dimensions (in inches) for North America, as well as the age groups and lifestyles they're best suited for. 

Small Single: 30" by 75"

Also known as a cot, a crib, or a toddler mattress, a small single is aptly named because it's the smallest available size for a mattress. It's the standard option used for cribs, but can also be transferred to most toddler beds as a child grows. When it comes to firmness levels, a small single mattress should be firm enough to stay flat, even if your child rolls around a lot. (This ensures the material won't get in the way of breathing.) Crib or toddler mattresses should also be made out of safe materials you can trust and should fit snugly in the base or bed frame to minimize the risk of suffocation. 

Twin: 38" by 75"

A twin bed is ideal for children, young teenagers, and those trying to optimize space in small living areas. It's also the most common mattress choice for bunk beds and daybeds, and has become a popular decorating trend for guest rooms when doubled up. (That way, it doesn't get awkward if your guests don't know each other that well.) As far as materials and firmness levels, your options are much more extensive compared to small singles; that's because the person sleeping in a twin is likely old enough to have a preference.

Pro tip: If you and your partner have vastly different ideas of what makes a comfortable mattress, you can combine two separate twin mattresses into a king using a strap kit like this. 

Twin XL: 38" by 80"

A twin XL is the most common bed size for dorm rooms and other college housing. That's because it saves space width-wise, but is taller to accommodate fully grown people. (By the way, if you're heading to college this year, you can check out these hacks to help you ace your dorm room.) Twin XL mattresses are also a good option for tall teenagers and adults in small bedrooms. Still, they're not as easy to find as other sizes, and even though they're technically bigger, the equal-to-twin width means they still can't comfortably accommodate couples.

Full: 54" by 75"

Also known as doubles, full beds are wider than twins and can sleep two people simultaneously if living space is especially tight. The width of this mattress will give each partner a little over two feet of sleeping room, so it's better suited for a single person in a moderately sized space. (It's also a good choice if you like to share the bed with your pets, because furry friends do have a tendency to take more than their fair share of space.)

You can also get something called a full XL, which is six inches longer than the standard full, but it's not very popular, nor is it easy to find in stores. 

Queen: 60" by 80"

A queen-sized bed is easily the most popular choice for all adult age groups, from young adults to senior citizens. That's because it allows for ample sleeping room (even for couples), but it won't take up all the space in a bedroom — so long as you have at least 100 square feet to work with. Since it's the most commonly used mattress size, accessories are readily available, so you'll have no problems finding a great set of sheets or a bed frame you love.

There's also something called an Olympic, expanded, or super queen, which is six inches wider than the regular, but again, it's a hassle to find and isn't considered standard sizing.

King: 76" by 80" 

A regular king is the widest standard mattress available — even wider than a California King — and its 76-inch width translates to over six feet of sleeping space. For that reason, it's the best option for partners who toss and turn, or in households with children who crawl into bed during the night. It's the second most popular mattress size, so finding sheets, a frame, and a gorgeous bedding set shouldn't be an issue. (You can also push two twins together to convert them into a king; the dimensions will be the same.)

As far as ideal room size, it's recommended that the space you're working with is at least 13 by 13 feet. Any smaller and you'll be face-to-face with a wall every time you get out of bed. 

California King: 72" by 84"

Finally, there's the California king mattress, which is four inches narrower than a standard king, but also four inches longer, too. This pick helps accommodate tall people, but it also makes a surprisingly big difference when your space is long and narrow. Despite its smaller width, it's big enough to fit extra family members or pets. It's also a good way to make a large bedroom feel cozy instead of cold and sparse. When offered as a sizing option for a mattress, this is typically the most expensive choice.

Common Types Of Mattresses 

Now onto the second half of Mattresses 101: mattress types and materials. Believe it or not, the kind of mattress you choose is even more important than the dimensions. Mattress materials dictate everything from firmness levels to breathability, so it's imperative that you do your research before you add one to your shopping cart. After all, it's a big investment, and it's one that'll impact your sleep quality, body temperature, and spine health for several years to come. 

While there are other types of mattresses, these options are the most common for a reason: They're specifically designed to keep you comfortable, safe, and well-rested. In addition to the individual features, benefits, and construction methods of each mattress type, I've also recommended a highly reviewed pick for each category. That way, once you've pinpointed which type is best for you, you can start shopping ASAP. 

Innerspring Mattresses

Innerspring mattresses have been used for centuries. They started out as a bunch of coils attached to a metal platform, but thankfully, designs have improved as technology has advanced. These types of mattresses are currently the most popular choice  (32 percent of adults use a spring mattress at home) because they're affordable and easy to find, both in-store and online. 

The word "innerspring" refers to the coils inside the mattress, which offer support, bounciness, and pressure relief. There are all kinds of coils that are commonly used, and their thickness and shape will determine the lifespan and price of the mattress. Above the coils, there's usually a thin layer of foam, padding, or fabric to cushion your body so you won't be able to feel the springs, which act as the core support system for your mattress.

When shopping for a spring mattress, there are three terms you should know: gauge, pitch, and coil count. Gauge is how thick the coils are (which correlates to firmness levels), pitch is the angle at which they're positioned, and coil count is how many springs there are in total. Consumer Reports states that the more coils a mattress has, the better, as it'll more effectively support your spine and conform to your body. On average, a quality innerspring mattress will last you roughly eight years.  

So what are the benefits of an innerspring mattress? In short, they're affordable, tried-and-true, and versatile enough to suit most firmness preferences. If you're on a budget, this one's likely the best option, as highly rated picks are available for as little as $100. 

The Jenna mattress by Modway is a great example of a quality innerspring. It features 15-gauge pocketed coils, which are considered the best option because they're individually encased in fabric and respond independently to pressure. As a result, they limit motion transfer and bounce while simultaneously conforming to your body.

Above the coils, the Jenna has a quilted top cover and two layers of foam padding. So far, reviewers have been thrilled. "My only complaint is that I don't want to get out of bed," one writes, while another buyer (who's had back surgery) says, "I've slept better on this than I ever did on my $1,000 mattress!" This pick is available in four sizes — twin, full, queen, and king — and ships straight to your door in a compact box. 

Modway Jenna Innerspring Queen Mattress, $220, Amazon.

Memory Foam Mattresses

Memory foam mattresses are the second most common choice for adults ages 18 to 60 and above. Thanks to the recent bed-in-a-box movement, they've gained tons of popularity. Their ability to compress and expand again is super convenient when it comes to shipping, delivery, and set-up. In other words, it's never been so easy to purchase a quality mattress without having to leave your house. 

Memory foam (also known as temper or viscoelastic foam) was actually created by NASA in the '70s to provide cushioning and protection in aircrafts. The first memory foam mattress was released in the 1990s, and companies have been improving upon the design ever since. Now, it's incorporated into everything from orthopedic pillows to shoe inserts, all because of the unique way it responds to weight and pressure. 

The key material in memory foam is typically a polymer called polyurethane, which (when dense enough) will mold to any shape in order to reduce pressure and evenly distribute weight. Thanks to its elasticity, however, it'll also return to its initial shape within a few seconds. For that reason, memory foam is one of the more durable materials for mattresses, and a good one could last you more than a decade. 

In addition, memory foam mattresses are usually considered the best choice for people who suffer from back pain. Because memory foam supports the concave curves of your back while simultaneously collapsing for  the convex areas, it conforms to your body and promotes proper spine alignment. This type of mattress is also one of the best options to use alongside an adjustable bed base because it's flexible, so it'll stay flush against the base in any position. (Another pro tip: Adjustable beds also help with back pain thanks to a feature called "zero gravity," which takes all the pressure off your spine. You can learn more about them here.) 

Now for a prime example of memory foam done right. The Tulo firm mattress feels "like floating on a very dense cloud," and for that reason, it's especially effective when it comes to spine alignment. Instead of a single layer, this mattress uses four: a firm memory foam foundation to fully support your body, an internal open-cell layer for optimal breathability, a memory foam top that relieves pressure, and a soft knitted cover that can be removed for washing. It comes compressed in an easy-to-transport box and expands to full size within a few hours. Despite the firm texture, it's compatible with most bed frames, including adjustable ones.

"This foam mattress is the best of the three I've slept on, providing necessary support with a lovely softness," one reviewer says. The Tulo comes in almost all standard sizes — twin, twin XL, full, queen, king, and California king. 

Tulo California King Firm Memory Foam Mattress, $984, Amazon.

Latex Mattresses

While latex mattresses are sometimes confused with memory foam mattresses, they're actually quite different. Instead of polyurethane, they're made from naturally sourced rubber from trees (or, unfortunately, synthetic substances that are designed to mimic it). These types of mattresses come in a variety of firmness options, but they tend to be more structured than memory foam and can support more weight. A latex mattress is also a good choice for a stomach sleeper because it retains its shape instead of sinking down on itself, and keeps the spine straight. Finally, if your partner tends to toss and turn during the night, latex will prevent motion disturbances and keep the mattress still, so they won't wake you up. 

The confusion surrounding latex mattresses has a lot to do with advertising. Many brands that are marketed as "latex" contain only a small layer over a memory foam or innerspring base, meaning that it's actually a hybrid — you can read more about those below. Furthermore, some companies use cheap petrochemicals that mimic the feel of latex to cut down on production costs; they throw in a tiny bit of natural latex so they can market it as such. Not only is the synthetic version less durable and not as supportive, but it also emits dangerous toxins that could be hazardous to your health. For that reason, it's really important to look for mattresses that are described as "all natural latex," or "100 percent pure." 

Natural latex mattresses can be one of the most expensive options, but they're also extremely durable. Some well-made designs can last as long as 25 years, and as long as they're made from tree-derived rubber, they're biodegradable, too. In fact, latex is potentially one of the most eco-friendly mattress options out there because it cuts down on waste pollution and removes excess carbon dioxide from the air during the growth process. 

The Pure Green mattress from Sleep On Latex doesn't use any synthetic materials at all. Instead, its 100 percent pure latex interior meets very strict production standards, and its exterior cover is made from a blend of organic wool and cotton. It also doesn't contain fire retardant chemicals or unpleasant odors like so many other mattresses do these days.

"I am over the moon happy with this mattress," says one of many five-star reviews."No more night sweats! No more sinking into the mattress and having to climb out. No more rolling toward the center! We sleep well and no longer have the aches, pains, and searing heat... High quality, dreamy mattress!" Consumer Reports has even given this pick an overall score of 81 and claim it's very good for a side sleeper and excellent for a back sleeper. It also eases movement and resists bounciness better than the average foam mattress. 

Sleep On Latex Pure Green Queen Mattress, $795, Amazon.

Hybrid Mattresses

This kind of mattress is exactly what it sounds like. Similar to hybrid cars, hybrid mattresses combine two or more different systems to give you a versatile design that suits various needs. The most common hybrid mattresses combine innerspring coils with memory foam or latex. They offer more bounce than a traditional all-foam mattress, which is great news for someone who hates that hot, sinking feeling. Thanks to a well ventilated layer of coils, they're also typically more breathable — but they still effectively support the spine due to memory foam's pressure absorption. Hybrid mattresses are usually not as loud as innerspring mattresses, either. That's because the foam helps to insulate the creaking of the coils. 

Since you're dealing with multiple materials here, it's important to do your research on all of them. Gauge and coil count will probably apply, since the majority of hybrid mattresses utilize springs as their main support system. However, you also need to keep firmness and density in mind. According to the Sleep Help Institute, memory foam usually has an indentation load deflection (ILD, or firmness level) of eight to 20, while latex has an ILD of 15 to 40. Softer materials like memory foam are better for lighter people and side sleepers while firmer latex layers work well for heavier people and stomach sleepers.

Hybrid mattresses are usually pricier and have an average lifespan of six years, but they're a great way to compromise if your partner has different sleeping preferences than you. 

Allswell is a bedding company that specializes in hybrid mattresses to give people the best of both worlds. By using individually wrapped coils and CertiPUR-US certified foam, they've created a medium-firm feel that provides support and comfort in any sleeping position. Its Luxe hybrid has a built-in plush mattress topper, special fabrics that stay cool to the touch all year, and a 12-inch frame that mimics expensive luxury brands — at a fraction of the price.

Last but definitely not least, it seems to be a crowd-pleaser for couples: "This mattress completely outdid my expectations. My husband was skeptical about a box mattress, but needless to say after a fun set up experience we both LOVED how it felt."

Allswell Luxe Hybrid, $585, Allswell.

Gel Mattresses

Also known as gel-infused foam, gel mattresses are yet another type of foam-based material — in fact, the production methods and contouring qualities are very similar to (if not the same as) memory foam. Basically, it's just viscoelastic infused with a phase-changing synthetic gel. Sometimes gel-infused foam is even paired with innerspring coils to create a hybrid mattress. Still, gel mattresses deserve their own category because, for people who overheat and sweat at night, they often make a massive difference in overall quality of sleep.

One of the biggest complaints about memory foam is that the dense construction traps body heat and moisture. If your body tends to run hot, this will probably leave you feeling uncomfortable, clammy, and wide awake. Cue the genius addition of gel, which became popular around 2011 and is now a go-to feature for mattresses, mattress toppers, and pillows. Not only does it supposedly cool the mattress by taking on the temperature of the room, but it's also designed to wick away sweat and allow for better ventilation through the material.

A good quality gel-infused mattress gives you all the benefits of a memory foam or hybrid — namely the support, comfort, and motion control — without any of the overheating. The Lull, for example, has several CertuPUR-US certified memory foam layers to cushion your body and align your spine, but the top layer is infused with a gel polymer that pulls heat away from your skin. When combined, you get a firm, supportive mattress that reviewers say "keeps the bed cool throughout the night." As far as Consumer Reports is concerned, it's worth an overall score of 78, and is comfortable for sleepers of all sizes and preferred positions.

You can get the Lull mattress in twin, twin XL, full, queen, king, or California King. They're all eligible for Prime's two-day shipping, and despite the compact box, they expand really fast. 

Lull Queen Memory Foam Gel Mattress, $800, Amazon.

Natural Mattresses

As the natural and organic movement progresses, people are realizing how much of an impact synthetic materials have on our health and environment. Not only do they produce wastes that can't be broken down on their own, but they contain byproducts and ingredients that may emit toxins into the air. (When your face is pressed up against said toxin-emitter for eight hours a night, that's not such a comforting thought.)   

Still, this presents a challenge. Up until recently, latex was one of the only popular materials used for natural mattress production, and since it has a firm, distinctive feel (and is a relatively common allergen), it's not a suitable choice for everyone.  Fortunately, more and more companies are now making an effort to produce worry-free bedding that uses alternative natural materials, and perhaps the biggest push for these products comes from parents. Crib safety is as big of a concern as ever, and since studies show that many children's mattresses let off some seriously scary chemicals, these safe, versatile materials are just in time. 

The Pebble Pure, for example, is one of the mattresses that's been making waves in the media. All the ingredients are non-toxic, sustainable, natural, water-resistant, and earth-friendly. (In fact, it meets the Global Organic Textile Standard, which, according to Consumer Reports, is one of the two best certifications a mattress can have.) It's also carefully designed for optimal ventilation so your baby can breathe safely in any position.

On the exterior, you'll find organic cotton and eucalyptus fiber for a machine-washable, hypoallergenic cover that's gentle on skin. On the inside, there's a thin layer of natural tree rubber latex, but you'll also find a core of organic coconut coir that provides ample padding and comfort without losing its shape. This mattress is even dual-sided — a firmer side for a young baby and a softer side for a toddler — so if you decide to move your child to a toddler bed, you can still use the Pebble Pure. Finally, since the mattress is infused with natural zinc, it helps minimize the growth of germs and bacteria so your child stays healthy. 

And parents rave about it. "As soon as we transitioned our baby into her crib she slept longer than she ever had. I love that I don't have to compromise her comfort and safety," one writes, while another says, "I love love love my Pebble Pure Mattress! I did a lot of research prior to buying and this is the most natural and healthy mattress on the market... It's so cozy yet firm and it is incredibly breathable." The crib-sized version comes in 11 gorgeous colors, and you can opt for the Pebble Lite (which uses non-toxic foam instead of latex) or the Pebble Air (which weighs less than the average newborn). The brand even makes an all natural, toxin-free twin mattress for children or teenagers. 

Nook Pebble Pure Crib Mattress, $195, Amazon.

Pillow-Top Mattresses

The mattresses in this subcategory are characterized not by what's inside of them, but what's on top of them. Also known as a box-top, pillow-top mattresses use one or a combination of the aforementioned materials to provide most of their support. They can be filled with foam, springs, gel, and latex. That said, it's the top few inches that set this mattress apart; it features soft padding that's designed to mimic a down pillow or a mattress topper, and this pillow-like consistency covers the entire surface of the mattress. (Note that because of this feature, most pillow-top mattresses can't be flipped over like those in other categories.) 

Needless to say, this is one of the softest options available. It's like lying on top of a massive body pillow, and it's a great option for those who prefer a traditional-feeling mattress or want to feel encompassed by comfort. On the other hand, it's not a great option for those who tend to overheat at night, as the pillow-like padding may trap excess body-heat instead of diffusing it. 

The Dormington mattress from Jubilee is a popular choice within this category. It's a hybrid, and it uses a combination of gel, memory foam, and pocket coils. This variety offers lots of support for any sleeping position — but the real selling point is the traditional pillow-top surface. The knit, tufted cover gives you a cushion-firm feel, and it's beautifully detailed with a fleur design and corded edges. This one also implements knit-side panels for breathability and ventilation, so in terms of pillow-top mattresses, it's one of the more cooling options. 

"This is a great mattress! LOVE that it still has inner springs in it, they're just more supportive," one reviewer writes. "The pillow top allows it to be super soft on top and the springs underneath make it firmer. Nice depth, it's not SO thick you can't get any sheets to stay on, but not too thin by any means." 

Jubilee Dormington Queen Hybrid Innerspring Mattress, $419, Target

Air Mattresses

Air mattressess are largely considered the best temporary options for guests and travel — but some people still choose to use air mattresses on a daily basis. For one, they're lightweight, portable, affordable, and can turn any room into a bedroom within mere minutes. For another, since they're filled with (you guessed it) air, it's extremely easy to customize the firmness level to your liking. 

It's important to note that air mattresses have improved by leaps and bounds in the last few years alone. (If you have unhappy memories of overworked lungs and waking up on a deflated lump of plastic, you can rest easy knowing that technology has since fixed those issues.) These days, most well-made air mattresses have built-in automatic pumps that get the job done within minutes, as well as features in place to stop them from deflating during the night. They're also usually made from thick, puncture-resistant materials that hold air for long periods of time. Finally, many brands have released extra-thick, raised designs, so you don't necessarily feel like you're sleeping on the floor. 

In terms of best-selling options, this Dream Series air mattress from SoundAsleep has an incredible 20,000 reviews on Amazon. That's largely because it provides all the features you need for a comfortable, convenient night's rest, wherever you happen to be.

For one, the patented one-click pump inflates the mattress in under four minutes and automatically deflates it just as fast. For another, the eco-friendly, waterproof PVC material is multi-layered, resistant to punctures, and stays inflated for days — plus the internal-coil design offers way more support than competing options. Last but not least, this air mattress has a SureGrip bottom and a double-height thickness, so it's easy to get into bed at the end of a long day. 

"By far the best air mattress we've ever owned," one reviewer writes, and judging by the thousands of other positive reviews, that seems to be the general consensus. Get it in twin, twin XL, queen, or king — each with its own compact travel bag.  

SoundAsleep Dream Series Queen Air Mattress, $120, Amazon.

Futon Mattresses

These types of mattresses aren't made for traditional bed frames, but instead for futons — a versatile piece of furniture that doubles as both a sofa and an impromptu sleeping space. Unlike sofa beds, which largely serve the same purpose, futons typically have removable, unattached mattresses which can be washed, rearranged, fluffed, and replaced. 

As a result, if you're looking for a more permanent sleeping solution in a small space, a futon may be the way to go.  They can be positioned upright for seating and compact storage during the day, but they lay flat for double the sleeping space when it's time for bed. Note that futon mattresses will vary in materials, colors, and thicknesses, but they all have one thing in common: They're flexible. This is so they can be creased down the middle when the futon itself is in an upright couch-like position. 

The Porch & Den Owsley futon mattress has some really great features at an affordable price. First, it's covered in breathable cotton and contains resilient foam filling; this is a huge step up from competitors, who often use synthetic covers and stuffing that quickly flattens out with weight. It's also significantly thicker than most other brands, which provides ample support and comfort whether it's being used as a couch or as a bed. 

This option fits most futon frames that open up into full-sized beds, and it's available in a huge range of colors. The tufted design adds an elevated appearance for your home office, guest room, or multipurpose living space. Most importantly, it has over 300 high ratings because it's comfortable, well-made, and stylish. 

Porch & Den Owsley Full Futon Mattress, $194, Overstock

Hyper-Elastic Polymer Mattresses

This one is without a doubt the newest, most innovative type of mattress. Much like pillow-top mattresses, these ones also use a combination of other materials for the lower layers, but the top layer is what sets it apart: hyper-elastic polymer. It aims to tackle common sleep issues (like lack of support and poor heat-distribution) using a unique, free-flow material. Constructed from allergen-resistant, non-toxic polymers, it looks almost like a beehive, but it's bouncy and supportive to ensure that your spine stays level in any position. It's also much more durable than foam and won't transfer motion, so it's a popular choice among light sleepers in long-term relationships. 

While other companies have since constructed similar designs, Purple is the creator and leading manufacturer of hyper-elastic polymer mattresses. Their Purple Hybrid Premier, for example, is considered one of the most adaptive, innovative choices on the market. While it features both high-density foam and responsive support coils, its success is largely due to the 4-inch hyper-elastic polymer purple grid, which took years to perfect. Basically, it's this layer that creates a cooling, low-gravity feel that's ideal for just about any sleeper. It's even guaranteed for up to 10 years under Purple's full warranty, and comes with free breathable sheets and a pillow. 

Currently, it has over 21,000 reviews and a 4.4-star rating. "My husband and I were both skeptical but hopeful when we ordered our Purple Hybrid Premier Mattress," one reviewer says. "Now that we've had our mattress for three weeks, we both agree that we would never go back to traditional mattresses." You can get it in two purple-grid heights and six size options.

Purple Hybrid Premier Queen Mattress, $2,999, Purple

Water Mattresses

A brief history of the waterbed: The first model was created in the 1800s. It was essentially a warm bath coated in rubber, and its main purpose was to reduce bedsores. Unsurprisingly, this design didn't really take off — but fast-forward to the '60s, when a student named Charlie Hall filled a mattress with Jell-O and cornstarch as part of his thesis. Before long, the water mattress could be found in department stores, bachelor pads, and suburban houses all around the country. 

While demand has admittedly tapered off, contemporary bedding companies have started to revisit the idea in order to create a supportive, adaptive mattress. In short, water adjusts to your weight while still providing enough support for your spine, so when combined with other materials, it could offer the high level of versatility that some sleepers need. (Some of Amazon's top-selling orthopedic pillows are filled with water, so why wouldn't the theory translate to full-body comfort?) 

Take, for example, Bali's Semi-Waveless water mattress system. This is not your average '70s waterbed. Yes, the top section is filled with liquid to create a weightless, floating sensation, but this option also has fabric-covered foam rails for better structure and support. It's also wrapped in a vinyl moisture barrier and wrapped again in an eco-friendly bamboo rayon fabric. Due to the included wood foundation and nine-leg steel frame, this is one of the few mattresses that comes with everything you need for a full set-up.

Bali Semi-Waveless Queen Water Mattress, $1,035, Overstock

Congratulations! You're now a graduate of Mattresses 101. We hope you found all the bed-related information you were looking for. So you know, Lonny may collect a share of sales from the links on this page.