King Mattresses
Shop award-winning king size foam mattresses for great sleep, at an even greater price.
How big is a king size mattress?
A king size mattress is 80 inches long and 76 inches wide.
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King
Dimensions: 76” x 80”
At 76 inches wide and 80 inches long, the king mattress is large enough to accommodate couples who share the bed with their children or a sizable pet (think: a Great Dane). A king bed can be made of two twin beds pushed together, which is referred to as a split king. King beds are large enough that both sleepers can sprawl out with room to spare.
Mattress Sizing Chart
Twin Mattress - 38" x 75" : Often found in kid's rooms and studio apartments.
Twin XL Mattress - 38" x 80": Often found in college dorm rooms and studio apartments
Full Mattress - 53" x 75": Often found in guest rooms.
Queen Mattress - 60" x 80": Often found in master bedrooms.
King Mattress - 76" x 80": Often found in extra large master bedrooms.
California King Mattress - 72" x 84": Often found in extra large master bedrooms, perfect for gathering the family.
Settling for an OK mattress? Dream bigger.
If you’ve never flopped down, and drifted off on a Casper King, it’s almost impossible to imagine this kind of regal comfort. The King size bed is a glorious 76 inches wide and 80 inches long, making it perfect for anyone who needs more sleeping space.
Precision engineered for astonishing comfort.
With multiple layers of breathable, feathery-soft memory foam, our king mattresses deliver cooling, weightless sleep. Our Zoned Support design cradles you weightlessly, for night after night of cloud-like slumber.
Who Should Get a King Size Bed?
Quality-built for years of dreaming.
Our standard King size mattresses are designed in the USA using premium materials, certified safe for your family and the environment. Oh, and they come with a 10-year limited warranty.²
Sprawl out & move around all you like
Casper mattresses will isolate your movement - thanks to proprietary foam technology. Larger than a Queen, you'll have enough room to not bother the person you're sleeping with.
King Size Hybrid Mattresses
Embark on a journey towards unparalleled comfort with our king size hybrid mattresses. Merging the adaptive support of encased springs with the plush coziness of memory foam, these hybrid king mattresses are crafted to mold to your body while offering a gentle lift. Our meticulous design champions seamless airflow, ensuring you stay cool as you drift off into dreamland. Explore below and uncover a harmonious blend of snugness, support, and cooling technology, perfectly tailored to elevate your sleep sanctuary.
Which Casper King Size Hybrid Mattress is right for you?
There are four versions to choose from if you're looking for a King. Our hybrid collection combines the pressure relief of our original foam with the added lift from resilient springs.
Dream Max
Our ultimate hybrid mattress with precision-cut foam and encased coils. Engineered with a gooey yet supportive medium-soft feel perfect for any sleep style—especially side sleepers.
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Snow Max
Our ultimate cooling hybrid mattress. Engineered with precision-cut foam and encased coils for a breathable and supportive medium-soft feel and Snow Technology for 12+ hours of cooler sleep.
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Dream
Combines the best of both worlds with resilient springs as the base for added lift and our proprietary foam for pressure relief. The "just right" feel is now even better.
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Snow
Our signature cooling hybrid mattress. Designed with soothing foam and encased coils for a supportive, medium feel plus Snow Technology for 12+ hours of cooler sleep.
Shop SnowKing Size Memory Foam Mattresses
Dive into a sea of calm with our King-Size Memory Foam Mattresses. Masterfully engineered with advanced memory foam technology, each mattress is a passport to a world where your body’s contours are cradled, easing life’s pressures as you rest. Our memory foam mattresses are your ticket to a sleep-friendly climate, striking a fine balance between embracing comfort and cool breathability. Browse below and discover a haven of sleep luxury that aligns with your unique comfort desires.
Which Casper King Size Memory Foam mattress is right for you?
If you're looking for an all foam mattress that doesn't sacrifice comfort, there’s a Casper king size mattress for you.
The One
The One was engineered using feedback and data from customers like you. If sleeping on a cloud sounds good, consider this your sweet spot.
Shop The OneMemory Foam vs. Hybrid King Size Mattresses
Memory foam king size mattresses are known for their exceptional body contouring and motion isolation, ensuring every sleeper feels cradled throughout the night. They offer a personalized sleep experience by molding precisely to your body, optimizing pressure relief.
Hybrid mattresses elevate the game by blending the unmatched comfort of memory foam with the robust resilience of springs. This combination results in a mattress that not only provides the coziness of memory foam but also ensures enhanced airflow, superior edge support, and a slightly buoyant feel.
Interested in learning more? Read through our comprehensive memory foam vs. hybrid mattresses guide.
Frequently asked questions
What’s the difference between a king and a California king?
The main difference between a king and a California king is the mattress size. A standard king mattress is 76" x 80", while a california king mattress is 72" x 84". If you’re deciding between the two, we recommend taking measurements to ensure the Cal king will fit, allowing enough space for the bed frame which can add inches to the perimeter of the mattress depending on the design.
How much bigger is a queen mattress than a full?
A split king mattress has the same dimensions as a standard king, but can be beneficial for couples who have different preferences or opt for an adjustable base. The combination of the split king mattress with the adjustable base enables both partners full control of their side of the bed while providing increased motion isolation.
Should I buy a queen or full bed?
When selecting a new mattress, the choice between a full or queen depends on your home, lifestyle, and sleep needs.
For most solo sleepers, both a full and a queen bed offer plenty of space. But if you want to be able to sprawl out and enjoy every inch of your luxurious mattress, then a queen is the way to go. For couples, the choice is more complicated. A full bed makes for a tight, cozy sleeping experience with two people, which some partners might actually prefer! For most couples, however, a queen bed adds those extra inches of breathing room necessary for comfort. For this reason, it’s typically seen as the best bed size for couples.
Naturally, room dimensions also factor into your choice of mattress type. If considering a queen bed, your room should be at least 10 x 10 feet to leave a comfortable amount of space around the mattress’ perimeter. In comparison, your room could be only 9 x 9.5 feet and still accommodate a full bed, or even smaller if you plan to fit your mattress into a corner.
Once you've decided on a full or queen size mattress, remember to consider other factors like the firmness level and special features before making a purchase.
Is a queen bed big enough for a couple?
In most cases, yes. At 60 x 80 inches, a queen mattress offers plenty of personal space for more than one sleeper.
There are a few exceptions to this rule, namely family homes and very hot sleepers. For couples with a child (or even a furry friend), you might need a king size bed mattress or larger to comfortably accommodate the extra bodies. If you're looking for a new mattress and either you or your partner tends to run hot at night, you might need the extra breathing room of a king bed—or a queen-size mattress with advanced cooling technology.
How Casper keeps prices low and quality high
When Casper was founded in 2014, many people were skeptical. Would consumers really buy a standard king size mattress without testing it first? Several years and numerous awards later, we have an answer: It turns out no one likes visiting stuffy mattress showrooms to make high-stakes purchases under the scrutiny of needy salespeople. (Who knew??)
Everyone loves the ease and convenience of buying online from a trusted source, and having a high-quality mattress shipped in a box to their doorstep. And people keep spreading the word that our mattresses deliver unparalleled comfort and support, top-notch construction quality, and high-tech, innovative design.
But the Casper experience isn’t just about quality, trust, and transparency. Our mattresses are a mere fraction of other brands’ prices. That’s because we’ve flipped the mattress industry on its head. By eliminating showrooms and middlemen, we keep our costs low - and pass those savings on directly to you.