8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (2025)

Table of Contents
Our Picks Best overall king-size mattress Brooklyn Bedding Signature Hybrid Best king-size memory foam mattress Nectar Premier Best firm king-size mattress WinkBed Best king-size mattress for couples Nest Bedding Sparrow Best king-size mattress for heavy people Big Fig Best affordable king-size mattress Allswell Best king-size mattress for back pain Saatva Rx Best king-size mattress for side sleepers Layla Hybrid What is the best king-size mattress overall? Video: Best king mattress for 2025 Best king-size mattresses of 2025 Best overall king-size mattress Brooklyn Bedding Signature Hybrid Best king-size memory foam mattress Nectar Premier Best firm king-size mattress WinkBed Best king-size mattress for couples Nest Bedding Sparrow Best king-size mattress for heavy people Big Fig Best affordable king-size mattress Allswell Best king-size mattress for back pain Saatva Rx Best king-size mattress for side sleepers Layla Hybrid Best king-size mattress firmness data How we test king-size mattresses Firmness Feel Temperature Motion isolation Edge support Special features What to consider when buying a king-size mattress Sleeping position and firmness Body and mattress type What we're testing next King-size mattress types King-size mattress FAQs How big are king mattresses? What brand of king-size mattresses is considered the best? How big should my bedroom be for a king-size mattress? Who is a king-size mattress best for? What's the difference between a king and California king mattress? What is the difference between a king and a split king mattress?

A king-size mattress is 76 inches wide and 80 inches long, offering plenty of room if you share the bed. The extra space can make a big difference in yoursleep experienceand help you get a restful night's sleep. With so many models on the market, CNET's sleep experts have done the legwork to help you choose the best bed for your sleep preferences, whether you want something firmer or a plush pillow top.

Many people struggle with sleep. In a recent CNET survey, six in 10 US adults said they would invest in a better sleeping setup. About half of adults surveyed said they'd even be willing to spend $1,000 per year to get better sleep. Making the right decision on a new mattress purchase can be a great way to invest in your sleep and overall health.

Our sleep experts have tested hundreds of beds from dozens of brands. We use a thorough and standardized method of evaluating each mattress. If price is a concern, don’t worry -- although king beds are more expensive, we’ve gathered solid choices for every budget. Here are the best king-size mattresses you can buy online.

Our Picks

How we sort our mattresses

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What is the best king-size mattress overall?

8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (9)

The Brooklyn Bedding Signature Hybrid ranks as our favorite overall king bed. With its various firmness options, this supportive hybrid mattress can accommodate all sleeping positions. It has a neutral foam feel that most sleepers will appreciate. Brooklyn Bedding often offers this bed at a discounted rate, making it also one of the best-value king-size mattresses.

Video: Best king mattress for 2025

Watch CNET sleep expertOwen Poolereview the best king mattresses for 2025.

Best king-size mattresses of 2025

Best overall king-size mattress

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8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (11)

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8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (12)

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8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (15)
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8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (17)
8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (18)

Pros

  • Suits all sleeping positions thanks to its firmness options
  • Hybrid construction supports all body types
  • Excellent bang for your buck

Cons

  • The optional pillow top is an extra $300
  • Not for those seeking a dense memory foam feel

Why we chose the Brooklyn Bedding Signature Hybrid: The Brooklyn Bedding Signature Hybrid suits all sleeping positions and offers a soft, neutral foam feel that most people like. It comes in three firmness options (soft, medium and firm), making it great for individuals and couples seeking an accommodating, supportive and durable mattress.

“Another thing that makes the Brooklyn Bedding Signature Hybrid an amazing bed is its price tag. Out of all the beds I’ve tested that have multiple firmness options, this is one is most of the most affordable -- discounts can bring this down to as low as $1,200. However, the bed never scarifies comfort or value,” says Caroline Igo, CNET sleep editor.

How it sleeps: The Brooklyn Bedding Signature Hybrid is made of high-quality foams and durable steel coils. Its innerspring construction allows for increased airflow, meaning it sleeps slightly cooler than an all-foam bed. It's cushioning yet responsive, making it easy to move around and switch positions.

The Soft model offers excellent pressure relief for side sleepers. Our Mattress Smasher 9000 ranked the Medium model 4.3 out of 10 on the firmness scale, so it is on the softer side but still accommodates all sleeper types, including combination. The Firm model is medium-firm or around 7 out of 10 -- best for back and stomach sleepers.

Runner-up: If you're a hot sleeper looking for a cooling king-size bed, check out the Brooklyn Bedding Aurora Luxe. It's one of the coolest mattresses we've ever tested (literally).

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Specs & Configurations

Type Hybrid mattress

Firmness 3 firmness levels | Soft: Medium-soft to soft or 2 | Medium: Medium to medium-soft or 4 | Firm: Medium-firm or 7

Trial 120 nights

Warranty 10-year limited warranty

Score Breakdown

Performance 8

Policies 7

Durability 8

Features 9

Best king-size memory foam mattress

Pros

  • Suitable for back, stomach and combination sleepers
  • Dense memory foam for those who like that hugging feel
  • Nectar Sleep offers a forever warranty

Cons

  • Might not be supportive enough for sleepers over 230 pounds

Why we chose the Nectar Premier mattress: If you're looking for a mattress with that slow contouring sensation, check out the Nectar Premier. This bed comes in hybrid and all-foam constructions, both offering a dense feel that memory foam lovers will enjoy. If you share the bed, its excellent motion isolation capabilities should keep you and your partner from waking each other up as you move throughout the night.

“Nectar Premier might be the most comfortable mattress I've ever slept on. As a side sleeper, I was looking for a plush bed with lots of pressure relief for my joints, and this is it. I don't wake up sore as I have on other beds, and I love the dense memory foam feel,” says Dillon Lopez, CNET senior video producer and mattress expert.

How it sleeps: Nectar offers its Premier mattress at an accommodating medium firmness level, confirmed by our Mattress Smasher 9000: both models received a firmness score of 4.9 out of 10, meaning it’s suitable for all sleeping positions. With a layer of innerspring coils, the hybrid version is slightly more durable and supportive, making it ideal for heavier individuals or couples.

Although it has a hugging, dense memory foam feel, it's still slightly more responsive than we expected, making it easier to switch positions. It's topped with a breathable cooling cover that we found to be more temperature-neutral than actively cooling.

Runner-up: If you want a softer bed or one with more cooling features, check out Nectar Luxe. For something firmer and cheaper, consider the Nectar Classic mattress.

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Specs & Configurations

Type Memory foam mattress

Firmness Medium to medium-firm or 6

Trial 365 nights

Warranty Forever warranty

Score Breakdown

Performance 9

Policies 8.5

Durability 7

Features 7

Best firm king-size mattress

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8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (27)

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8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (28)

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8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (31)
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8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (34)

Pros

  • Accommodates all sleeping positions and body types
  • Great price for the quality
  • Cloud-like pillow top
  • Supportive and durable

Cons

  • Not a true budget option
  • Not for those who want a memory foam feel

Why we chose the WinkBed mattress: WinkBed is a high-quality, American-made hybrid mattress with a reasonable price tag, and its Firm model takes the crown for the best firm king bed. With pocketed coils and multiple zones of targeted back support, it's plenty durable and comfortable.

CNET sleep and mattress expert Taylor Leamey explains, “If I’m going to sleep well at night, it has to be on a pillow top. WinkBed has one of the softest pillow tops I’ve ever tested. Not to mention, it’s an exceptionally durable bed that’s well-priced. While I wouldn’t call it a budget bed, you get more than your money’s worth.”

How it sleeps: If you like the feel of a plush and airy pillow top, you'll love the WinkBed. It's responsive yet cushioning, and its eco-friendly Tencel cover is breathable and soft.

We love to see options when it comes to mattress firmness, and WinkBed offers four different profiles to choose from: Softer, Luxury Firm, Firmer and Plus. The Luxury Firm version is a medium on our scale (rated 5.8 out of 10 by our Mattress Smasher), making it suitable for all sleeping positions. If you're on the heavier side, the Plus model might be the best choice for you -- the heavier you are, the more you'll sink into the mattress and the softer it will feel. Our Smasher ranked the Plus model 6.5 out of 10, tipping into medium-firm

Runner-up: The Saatva Classic is another firm king-size mattress option if it's within your budget. For $2,599, it's more expensive than the WinkBed, but we think it's a great choice if you're looking for something a little more luxurious.

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Specs & Configurations

Type Hybrid mattress

Firmness 3 firmness levels | Softer: Medium-soft (3) | Luxury Firm: Medium (5) | Firm: Medium-Firm (7) | Plus: Firm (8-9)

Trial 120 nights

Warranty Lifetime warranty

Score Breakdown

Performance 8

Policies 9

Durability 9

Features 9

Best king-size mattress for couples

8.5 /10

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8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (35)

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8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (39)
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8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (41)
8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (42)

Pros

  • Split firmness options for the king sizes
  • Excellent policies, including a lifetime renewal exchange
  • Durable hybrid construction

Cons

  • On the more expensive side
  • Not for those seeking a memory foam feel

Why we chose the Nest Bedding Sparrow Signature Hybrid: Thanks to its dual firmness capabilities and lifetime renewal exchange program, the Sparrow Signature Hybrid from Nest Bedding is a particularly great option for couples. Each side of the bed can have a different firmness level for partners with varying sleep positions and preferences. This unique feature is only available in the Sparrow Hybrid's king and California king sizes, which is why it's the best king-size mattress for couples.

How it sleeps: If you and your partner are lucky and prefer the same firmness level, it's available in Plush, Medium and Firm. Our mattress experts felt the Medium model to be on the softer side, which was confirmed by the Mattress Smasher's score of 3.75 out of 10 on the firmness scale. The Sparrow has a bouncy and responsive pillow-top feel, so it's easy to switch positions and move around.

Nest Bedding has some of the best company policies we've ever seen, including a 365-night trial period, free returns and a lifetime renewal exchange program. This allows you to exchange the bed's comfort layer to increase its lifespan or change the feel and firmness if it's not working for you.

Runner-up: If you and your partner can't agree on a mattress type, check out Helix Sleep. The brand offers a large assortment of mattresses with different makes and firmnesses, and its sleep quiz can help determine which bed is best for both of you.

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Specs & Configurations

Type Poly foam hybrid

Firmness 3 firmness levels available

Trial 365 nights

Warranty Lifetime warranty

Score Breakdown

Performance 8

Policies 9

Durability 8.5

Features 8.5

Best king-size mattress for heavy people

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8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (43)

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8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (44)

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8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (47)
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8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (49)
8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (50)

Pros

  • Extremely durable and supportive
  • Great value for its quality construction
  • Excellent for back and stomach sleepers

Cons

  • Not recommended for side or combination sleepers
  • Not for those wanting a memory foam feel

Why we chose the Big Fig mattress: Big Fig is an independent online mattress brand that makes beds specifically for those with bigger bodies. Heavier individuals and couples need a supportive and durable mattress, and Big Fig's heavy-duty pocketed coils and high-density foams are designed to support up to 1,100 pounds.

How it sleeps: How firm a mattress feels will vary depending on how heavy you are. We found Big Fig to be around a medium-firm to firm for the average-size person and slightly softer the heavier you are. Our Mattress Smasher ranked it a 6 out of 10 for a body weighing around 165 pounds.

This hybrid mattress is super responsive and has excellent edge support. Since it is firmer, there's not much pressure relief, so we wouldn't recommend it for strict side sleepers; instead, its supportive construction makes it ideal for back and stomach sleepers.

Runner-up: For heavier side sleepers looking for an alternative, check out the new Nectar Luxe Hybrid mattress.

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Specs & Configurations

Type Hybrid mattress

Firmness 8 or medium-firm to firm

Trial 120 nights

Warranty 20-year warranty

Score Breakdown

Performance 8

Policies 8.5

Durability 9.5

Features 8

Best affordable king-size mattress

7.6 /10

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8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (51)

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8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (57)
8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (58)

Pros

  • One of the most affordable hybrid beds on the market
  • Suits back, stomach and combination sleepers
  • Accommodating for all body types

Cons

  • A little too firm for side sleepers
  • Only one firmness option

Why we chose the Allswell mattress: Finding a hybrid king-size mattress under $600 is a challenge, which is why Allswell wins as the best affordable king bed on this list. Sold for $599 at Walmart (often less than that during sales), this low-budget bed-in-a-box offers insane bang for your buck.

How it sleeps: The construction of this 10" thick mattress is fairly simple: a foam base layer underneath the 6-inch-tall pocketed coil system, topped with a layer of gel memory foam. It doesn't have the sinking sensation of memory foam but has a more neutral foam feel. The Allswell responds quickly to pressure and allows you to easily switch positions throughout the night, which is great news if you're a combination sleeper.

Thanks to its hybrid construction, it's suitable for all body types and falls slightly into the medium-firm category (our Mattress Smasher 9000 gave it a 6 out of 10 on the firmness scale). It can generally accommodate all sleeping positions, particularly back, stomach and combination.

Runner-up: For another affordable option, check out the Dreamfoam Doze mattress by Brooklyn Bedding. At $260 for a king, it’s the cheapest we’ve seen. With its neutral foam feel and medium-firm firmness, it’s an accommodating choice.

Overall, the Allswell mattress is a solid, wallet-friendly option.

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Specs & Configurations

Type Hybrid mattress

Firmness 6 or medium to medium-firm

Trial 100 nights

Warranty 10-year limited warranty

Score Breakdown

Performance 8

Policies 6.5

Durability 7

Features 9

Best king-size mattress for back pain

9 /10

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8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (59)

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8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (65)
8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (66)

Pros

  • Noticeable zoned support
  • Unique features like foam-topped coils and an additional micro coil layer
  • Designed specifically to relieve back pain

Cons

  • Expensive
  • Only one firmness option

Why we chose the Saatva Rx mattress: Our take: Your mattress can make all the difference if you live with chronic back pain -- enter the Saatva Rx. Specifically designed to alleviate pain from health conditions like scoliosis, sciatica and arthritis, it has noticeable zoned support and pressure relief in all the right places.

How it sleeps: We could immediately feel the zoned support of the Saatva Rx when testing this mattress. It has a comfortable pillow-top feel with a hint of memory foam, so it's cushioning and plush yet still responsive. It offers good pressure relief for your joints and is an excellent choice for combination sleepers with back pain. At 6.1 out of 10, the Mattress Smasher 9000 scored this bed slightly firmer than we expected but is still in that accommodating medium range.

Its unique features include foam-tipped coils, an extra layer of flexible 1" micro-coils and gel memory foam lumbar support for helping to keep your spine in neutral alignment. This construction is intended to eliminate pressure points and improve circulation.

At $3,999 for a king, this is certainly not a budget-friendly option. However, if you're living with back pain and want to try this premium bed, Saatva offers discounts around holidays that will knock the price down. The brand also offers a 365-night trial period with a $99 fee if you need to return or exchange your mattress.

Runner-up: If you're looking for something firmer (and cheaper), the Saatva Classic mattress is a nice alternative that still provides enough support for those seeking a mattress that can help relieve back pain.

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Specs & Configurations

Type Hybrid

Firmness Medium

Trial 365 nights

Warranty Lifetime warranty

Score Breakdown

Performance 9

Policies 8.5

Durability 9.5

Features 9

Best king-size mattress for side sleepers

8.5 /10

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8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (67)

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8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (74)

Pricing based on Queen model

Pros

  • Flippable design allows for two firmness levels in one bed
  • Great pick for side sleepers who want a plush, light and airy feel
  • Suitable for all body types

Cons

  • Heavy back and stomach sleepers will likely think it's too soft

Why we chose the Layla Hybrid mattress: Layla Sleep frequently appears on our CNET best lists for good reason. Its Layla Hybrid mattress is unlike most other hybrid mattresses in that it's flippable, and each side is designed to be slept on. One side is firmer, rated 5.3 out of 10 by the Mattress Smasher, while the other is softer, landing at 3.1 out of 10.

How it sleeps: We describe the Layla Hybrid's feel as an airy, responsive memory foam. It still provides some sinking, contouring sensation but less than the typical denser, more viscous memory foam. The soft side is perfect for side sleepers seeking that plush, pressure-relieving feel. Although Layla calls the flip side "firm," it's more of a medium to medium-firm on the firmness scale. It will provide a little more support than the soft side, still offering pressure relief, which makes it a great choice for heavier side sleepers who want a soft and supportive mattress.

So, how is this mattress flippable? In the middle of the Layla Hybrid is a layer of pocketed coils with varying layers of foam on either side, including copper-infused memory foam intended to help regulate body temperature.

Runner-up: If you don't care about coils and are looking for a more traditional memory foam feel, check out the Layla Memory Foam mattress.

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Specs & Configurations

Type Flippable hybrid mattress

Firmness 6 or medium to medium-firm | Soft: 3 or medium-soft

Trial 120 nights

Warranty 10-year limited warranty

Score Breakdown

Performance 9

Policies 8.5

Durability 8.5

Features 8

Best king-size mattress firmness data

Here at CNET, we test mattress firmness in subjective and objective ways to thoroughly assess how it feels and who it's best for. Subjectively, we use our experience and expertise to test and analyze a bed's construction, describing where it lands on the firmness scale to the best of our ability. How a mattress feels to me may differ drastically from how it feels to you, which is why we describe firmness from the perspective of varying body types and sleeping positions.

8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (75)

The Mattress Smasher 9000 is a proprietary CNET device that objectively assesses mattress firmness. This unique machine presses down into the mattress with a predetermined amount of force (to simulate whatever body weight we are testing), calculating how far its arm goes into the mattress to determine its firmness on a scale of 1 to 10.

The Allswell is the firmest bed on our best king-size mattress list, at 6.3 out of 10. The softest, at 3.1, is the Soft side of the flippable Layla Hybrid bed.

How we test king-size mattresses

Our sleep experts have been testing mattresses, bedding and accessories for years (a few have been testing for up to eight years). At this point, we've tested over 300 mattresses from dozens of brands, from bigwigs like Purple and Tempur-Pedic to more niche companies like Sonu and Airweave.

Our team is comprised of bed testers with varying body weights and types, heights, genders and sleep preferences, which helps us provide an overarching assessment of each mattress from a multitude of viewpoints. Many mattresses are tested for long periods, ranging from a month or two up to five years.

We test king-size mattresses just like we would any other bed. When a new mattress arrives at our testing facility, it undergoes rigorous, hands-on testing by each of our experts. We analyze specific characteristics, including firmness, feel, temperature, motion isolation, edge support and other special features the mattress may have.

Firmness

Firmness is rated numerically on a scale of 1 (the softest) to 10 (the firmest), and we use industry terms such as soft or medium-firm to describe it. Our entire team takes turns assessing and ranking the firmness of each mattress, which allows us to make suggestions about which sleeping position and body type it best suits. After subjectively analyzing the firmness, we let our one-of-a-kind Mattress Smasher 9000 do its thing and give us an objective firmness score.

8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (76)

Feel

Another subjective element we review is the feel of a mattress, separate from its firmness. Does it feel springy and responsive when lying on it? Is it easy to switch positions? Or does the dense memory foam conform around our bodies and hold our shape for a while? Does the mattress have a soft, plush pillow top feel, or is it more neutral? Can we feel any coils or zoned support? We do our best to describe exactly what it feels like to lie on each bed to help you determine if it's right for you without having to test them all yourself.

Read more: Why the Foam in Your Mattress Matters

Temperature

Temperature can be tricky to review when considering each sleeper's personal preferences and the fact that many mattress brands exaggerate their beds' cooling capabilities. When testing and reviewing mattresses, we detail how hot or cool the mattress sleeps. Many external factors come into play here (such as climate and environment, bedding, pajamas, etc.), so we test the beds in temperature-controlled rooms without sheets or bedding. Using our extensive knowledge and experience, we analyze its construction and materials and explain how they affect the temperature.

Motion isolation

8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (77)

Motion isolation is a term we use to describe how well the mattress deadens movement across its surface. It's an especially important feature for light sleepers or those sharing the bed with a partner or pets. We test its motion isolation capabilities by having one expert lie on the bed while another flops around and switches positions. The second method is by setting a glass of water on the edge, rolling toward and away from it to see if the glass tips or falls over.

Edge support

Edge support is typically not as important for king-size mattresses as it is for smaller sizes such as queen or twin. Regardless, testing the edge support allows us to assess how well it holds its structure and support around the perimeter. We sit and lie on the edge to see how the bed responds. Does it cave in and give the sensation that we'll roll off, or is it sturdy and supportive? We also push down on the edges with our fists to observe how much the edge compresses under pressure.

Special features

Some brands include special features in their mattresses, such as cooling covers for hot sleepers or zoned support for those with back pain. We test and review these additional characteristics and determine which type of sleeper would benefit the most.

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What to consider when buying a king-size mattress

The mattress market is massive, and determining the best bed for you is no simple task. To help narrow down your search for the best king-size mattress, here are a few key considerations to keep in mind.

Sleeping position and firmness

One of the first things you should know is how firm you want your mattress to be. Your sleeping position plays a large part in determining this. The firmness scale ranges from 1 to 10, with 10 being the firmest. A bed on the high end of the range, such as the Plank Firm Luxe, will feel extremely supportive and "hard" -- you won't sink into it much. Typically, this is best for strict back and stomach sleepers as it will help keep your spine and neck neutrally aligned.

On the flip side, a softer mattress has more cushioning, and you will sink into it more than a firmer mattress. That's why softer mattresses are generally recommended for side sleepers who need pressure relief around the shoulders and hips.

A bed in the medium firmness range can accommodate most sleeping positions, including combination sleepers who move around throughout the night. If you aren't sure what you prefer, here's how to find your personal Goldilocks bed firmness.

Body and mattress type

Like humans, mattresses come in all sizes and types, from all-foam beds to hybrid mattresses with coils and foam. Knowing the right mattress type for you depends on how you want it to feel. Do you like the feel of viscous, hugging memory foam that conforms around your body as you sink into it? Or do you prefer to lie more "on top" of a bed with a neutral foam feel? Do you like soft and plush pillow-top covers? It's preferential, and knowing this will help you eliminate beds in your search for the best king-size mattress.

A bed's firmness and feel can be subjective based on body type and weight. The more you weigh, the further into the bed’s layers you’ll sink and the softer it may feel. Conversely, the lighter you are, the more you’ll lie on top of the mattress, which can make it feel firmer. and the construction of the mattress matters here.

All-foam beds typically have less support and durability than hybrid beds with coils and foam. We recommend heavier individuals and couples look for hybrid mattresses as they're generally more durable and tend to last longer. If you're a heavier person looking for a memory foam feel, don't worry -- there are tons of great hybrid beds with dense memory foam layers on top.

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What we're testing next

8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (78)

At our large warehouse in Reno, Nevada, the mattress testing never stops. We are constantly receiving and reviewing new mattresses and updated beds from tons of different brands. Some of the brands we’re currently testing new beds from include:

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King-size mattress types

King and California king-size mattresses are the most popular king mattresses, but a host of other beds fall under the this category. If you're looking for a slightly different measurement, here are the various types of king beds.

Read more: Your Guide to Fitting a King Bed in Your Bedroom

TypeDimensions
Standard king (aka Eastern king) 76 x 80 inches
California king 72 x 84 inches
Split king Two twin beds (38 x 80 inches)
Split California king Two twin XL beds (38 x 84 inches)
Alaskan king 108 x 108 inches
Wyoming king 84 x 84 inches
Texas king 80 x 98 inches

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King-size mattress FAQs

How big are king mattresses?

A king-size mattress measures 76 inches wide by 80 inches long by 76 inches wide. It’s the same length as a queen-size mattress but has an additional 16 inches in width.

What brand of king-size mattresses is considered the best?

Considering there are usually two sleepers on a king-size mattress, the best king bed should typically have pocketed coils, reinforced edge support, good motion isolation capabilities and a breathable or cooling cover. After extensive testing, we chose a model from Brooklyn Bedding as the best overall king-size mattress.

Some brands that we also liked were: WinkBed, Nectar, Layla and Casper.

How big should my bedroom be for a king-size mattress?

A king-size bed is 76 inches wide by 80 inches long, or 6.33 feet wide by 6.66 feet long. It’s recommended that your bedroom be at least 12 by 12 feet in order to comfortably fit such a large bed.

Who is a king-size mattress best for?

In general, a king-size mattress is a great option for couples who want more sleeping space than a queen offers or for people sharing a bed with their kids or pets. They’re also great for taller people who want more foot and headroom. And if you have the space for an aesthetic choice, a king-size mattress makes quite the statement in a bedroom.

What's the difference between a king and California king mattress?

A king and California king-sized mattress are both bigger mattresses. However, a California king isn't as wide, giving you more space at the foot of the bed instead. This is good for taller individuals or those who have animals that will sleep at the foot of the bed.

What is the difference between a king and a split king mattress?

A split king is a king-size mattress made up of two twin beds placed side-by-side. Both a traditional king-size mattress and a split king are 76 inches wide by 80 inches long. Couples sometimes opt for a split king mattress setup to reduce motion transfer between the two sides of the bed or when each person has significantly different mattress preferences (such as firmness, support needs, etc).

8 of the Best King Mattresses of 2025, Tested by CNET Sleep Experts (2025)
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