The Best King Size Mattresses of 2021 (Reviewed & Compared)

Sleep Like a King!

January 14, 2021

To help you find a mattress of your dreams, our team of expert reviewers analyzed 22 hybrid mattresses, 19 foam beds, and 7 innerspring mattresses. After thoroughly examining their features, we compiled a list of the top 10 best king size mattresses based on the most important criteria:

  • Comfort level
  • Quality
  • Trial period and return policy
  • Warranty
  • Price

We also prepared a simple yet comprehensive guide to assist you in the shopping process. Here, you can find all the things you need to consider before you set your mind on any particular mattress.

Our Top 3 Picks

A Quick Overview of Our Top 10 Picks

Company
Features
Overall Score
Puffy Logo
Editor's Pick
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    High level of body contouring

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    Stain-resistant cover

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    Made in the USA

Amerisleep Logo
Excellent Pick for Side Sleepers
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    Targeted pressure relief

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    Cooler than traditional foam

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    Eco-friendly

Nectar Sleep Logo
Best Value
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    Excellent at isolating motion

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    Deep body contouring

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    Below average price tag

Nuvanna Logo
Budget-Friendly Option
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    Great contouring

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    Good temperature regulation

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    Great motion isolation

Casper Logo
Perfect for Spinal Alignment
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    Great pressure relief

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    Zoned support

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    Excellent at isolating motion

Live and Sleep Logo
Luxury Mattress
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    Excellent at isolating motion

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    Great contouring

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    Minimal sinkage

Saatva Logo
Stellar Innerspring Mattress
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    High level of personalization

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    Luxurious mattress at a reasonable price

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    Great temperature regulation

Nest Bedding Logo
Best Edge Support
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    Excellent temperature regulation

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    Three firmness levels

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    Internal split option

Leesa Logo
Amazing Pick for Hot Sleepers
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    Good spinal support

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    Excellent at isolating motion

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    Doesn’t sink too much

Tempur-Pedic Logo
Perfect for Couples
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    Excellent motion isolation

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    Three firmness levels

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    Removable cover

King Size Mattresses Reviewed

If you’re looking for a king size mattress, you have come to the right place. Below you can find all the information you need to make the right decision. 

Puffy Lux Hybrid Mattress

Puffy Lux Hybrid Mattress
  • Editor's Pick

  • Type: Memory foam

  • 101-night trial

  • Lifetime warranty

  • Free shipping

  • Price: $1,999

PROS :
  • High level of body contouring

  • Stain-resistant cover

  • Made in the USA

CONS :
  • Too soft for stomach sleepers

The Puffy Lux is a fantastic option for sleepers who enjoy a “deep hug” of memory foam, which contours to their body curves. The mattress is made up of four foam layers and contour-adapt coils, which provide a good level of spinal support and pressure relief.

Thanks to memory foam, it conforms to a sleeper’s body in all sleeping positions. However, since it’s a bit on a softer side, we wouldn’t recommend it to stomach sleepers.

Besides exceptional comfort, the Puffy Lux performs great when it comes to motion isolation. That’s probably one of the reasons why it’s so popular among couples.

Also, you should know that all the foams are CertiPUR-US Certified, meaning they don’t contain any toxic chemicals. Another proof that Puffy is using only high-quality materials is its lifetime warranty. This clearly shows that the manufacturer strongly stands behind its products.

Amerisleep AS3 Mattress

Amerisleep AS3 Mattress
  • Excellent Pick for Side Sleepers

  • Free shipping

  • 100-night trial

  • 20-year warranty

  • Price: $1,899

Rating 9.8

Get the Best Deal
PROS :
  • Targeted pressure relief

  • Cooler than traditional foam

  • Eco-friendly

CONS :
  • A bit pricier

If you’re looking for the best value for your money, Amerisleep AS3 might be a great option. This mattress offers a medium-firm feel, meeting the needs of most sleepers. However, if you prefer a softer or firmer feel, Amerisleep offers four more models, so you should check them out.

AS3 features three foam layers, which are designed to provide both excellent support and pressure relief. Thanks to its targeted support technology, the mattress will keep your spine properly aligned without causing additional pressure to your hips and shoulders. Therefore, it’s an excellent pick for side sleepers.

Being an all-foam bed, AS3 isolates motion pretty well. So, if your partner is a restless sleeper, you won’t have to worry about all that tossing and turning. Also, it has pretty solid edge support when compared to other foam mattresses.

Another cool option for couples is a split king mattress, especially if you’re using an adjustable base. This way, you and your partner can each adjust the base according to your needs.

Nectar Mattress

Nectar Mattress
  • Best Value

  • Type: Memory foam

  • 365-night trial

  • Forever warranty

  • Free shipping

  • Price: $1,498

Rating 9.9

Get the Best Deal
PROS :
  • Excellent at isolating motion

  • Deep body contouring

  • Below average price tag

CONS :
  • Too much sinkage for some sleepers

This young company, which was founded only a couple years ago, has quickly become established in the competitive mattress-in-a-box industry. If you’re a memory foam fan who prefers mattresses with a deeper hug, the Nectar is the right choice for you. 

We believe people with lower back pain will find this memory foam mattress exceptionally comfortable. This is because the mattress provides great support and some nice cushioning at the same time. We’d recommend it to back and side sleepers, while stomach sleepers typically need less sinkage.

Since the Nectar uses a Tencel cover and gel memory foam in its first layer, it sleeps cooler than most foam mattresses. Therefore, it’s a good option even for hot sleepers. Couples will also be happy to hear that this king size mattress absorbs motion very well.

Considering that the manufacturer offers an entire year to test your mattress, there’s really no risk in giving it a try. What’s more, the Nectar comes with a lifetime warranty, which should give you peace of mind if you decide to buy it.

Nuvanna Mattress

Nuvanna Mattress
  • Most Affordable

  • Type: Foam

  • 100-night trial

  • 10-year warranty

  • Free shipping

  • Price: $950

Rating 9.6

Get the Best Deal
PROS :
  • Great contouring

  • Good temperature regulation

  • Great motion isolation

CONS :
  • Only one firmness level

Nuvanna is still rather new in the mattress-in-a-box market. Nevertheless, it offers an amazing mattress at a very affordable price.

It’s an all-foam mattress, which has a medium-firm feel. As you will see below, people often choose different firmnesses depending on their preferred sleeping position. While stomach sleepers might be looking for the best firm king size mattress, this all-foam mattress will suit most side and back sleepers.

The Nuvanna mattress is comprised of three layers that are designed to provide maximum comfort. The high-density polyfoam in the base layer provides great support, while the memory foam and gel-infused polyfoam in the comfort layer allow for some nice pressure relief. The mattress is topped with a Tencel cover, which is very soft and breathable.

Even though the construction of the mattress is made of different types of foam, the bed has a pretty good temperature regulation. Also, if you or your partner is a light sleeper, you should know that this king size mattress might be a great pick because it isolates motion very well.

The good news is you can test this mattress at home for more than three months and then decide if you like it or not. Even better, it comes with a 10-year warranty.

Casper Original Mattress

Casper Original Mattress
  • Perfect for Spinal Alignment

  • Type: Foam/hybrid

  • 100-night trial

  • 10-year warranty

  • Free shipping

  • Price: $1,295

Rating 9.7

Get the Best Deal
PROS :
  • Great pressure relief

  • Zoned support

  • Excellent at isolating motion

CONS :
  • Lacks bounce

Casper is one of the most renowned mattress brands in the industry. It offers four mattress models—the Wave, the Nova, the Original and the Element. However, the Casper Original probably sells the most since it offers great comfort for a reasonable price.

In its original version, it consists of four layers designed to keep the body in perfect alignment without adding additional pressure to sensitive points, such as the hips and shoulders. This is why it’s a great pick for side sleepers, although back and stomach sleepers won’t be disappointed either. Its versatility is just one of the factors which make it our top choice overall.

In fact, it boasts a Zoned Support foam that provides exceptional support to your back, while allowing pressure relief for your hips and shoulders. Many customers praise this feature since it relieves their aches and pains, and helps them have a great night’s rest.

Furthermore, the Casper has excellent motion transfer, which makes it perfect for couples. However, if you’re on the heavier side, we’d recommend opting for a hybrid version because springs offer stronger support. Casper also offers king size bedding that will perfectly fit your mattress.

Live and Sleep Mattress

Live and Sleep Mattress
  • Luxury Mattress

  • Type: Memory foam

  • 100-night trial

  • 20-year warranty

  • Free shipping

  • Price: $999

Rating 9.7

Get the Best Deal
PROS :
  • Excellent at isolating motion

  • Great contouring

  • Minimal sinkage

CONS :
  • Not ideal temperature regulation

Live and Sleep offers three all-foam mattresses. Although each has its advantages, we believe that the Luxury Mattress is Live and Sleep’s best because it suits so many sleepers. It’s medium-firm, so most customers are satisfied with the feel it offers. Under its soft breathable cover, the mattress consists of three foam layers, which all work together to provide exceptional comfort. 

On top of that, there’s minimal sinkage even though it’s a memory foam mattress, so combination sleepers can easily change their positions during the night. Thanks to its great support, the mattress will keep your body in perfect alignment, while its top memory foam layer contours to your body shape and provides pleasant pressure relief.

It’s also great that it absorbs motion pretty well, so couples are able to have a great night’s sleep even if one of them is a restless sleeper.

Although Live and Sleep’s Luxury Mattress isn’t a cheap mattress, it is one of the few affordable king size mattresses that can boast such a luxurious look and feel. If you’re still having doubts, keep in mind that this manufacturer offers a 100-night trial during which you can test the mattress out and return it if you’re not satisfied. In addition, the mattress is covered by a 20-year warranty, which isn’t a small thing.

Saatva Classic Mattress

Saatva Classic Mattress
  • Stellar Innerspring Mattress

  • Type: Innerspring

  • 120-night trial

  • 15-year warranty

  • Free shipping

  • Price: $1,899

Rating 9.8

Get the Best Deal
PROS :
  • High level of personalization

  • Luxurious mattress at a reasonable price

  • Great temperature regulation

CONS :
  • Average motion isolation

Saatva is another company well-known for its luxurious mattresses. Thanks to its quality and reasonable pricing, the Saatva Classic mattress has become very popular in the mattress-in-a-box world. Thus, it has easily earned a place on just about any list of the most comfortable mattresses

This innerspring model consists of three layers: two different types of coils separated by foam and a Euro pillow top. Its “coil-on-coil” technology makes the mattress extremely supportive, so it will keep your spine in proper alignment no matter your sleeping position.

We also like that the mattress cover is made of organic cotton. Besides being soft to touch, it’s very breathable, which promotes good airflow.

This luxurious pillow top mattress comes in three firmness levels and two thickness options, which you can choose between depending on your sleeping position and any other sleeping preferences. It’s amazing that you can personalize your mattress at no additional cost. With this in mind, we can say that Saatva offers the best prices in the luxury category.

While the Saatva mattress excels at temperature regulation, it isn’t that good at isolating motion. We’d say this is somewhat expected since innerspring mattresses are bouncier than foam mattresses. While we wouldn’t recommend this mattress to light sleepers, it’s a great choice for those whose main priority is a healthy sex life.

Nest Alexander Hybrid Mattress

Nest Alexander Hybrid Mattress
  • Best Edge Support

  • Type: Hybrid

  • 100-night trial

  • Lifetime warranty

  • Free shipping

  • Price: $1,799

Rating 9.8

Get the Best Deal
PROS :
  • Excellent temperature regulation

  • Three firmness levels

  • Internal split option

CONS :
  • Heavy and difficult to move

Nest Bedding is a well-established mattress-in-a-box company that was founded in 2011. It has been doing well on the market for a while now, and for good reason. It offers a wide range of mattresses, all of which are made of high-quality materials.

The Alexander Signature Hybrid is made of five layers, which are all there to make you comfortable and help you have the best night’s sleep. 

The combination of coils and foam layers has a number of benefits. While innerspring mattresses don’t perform so well when it comes to motion transfer, this hybrid mattress absorbs motion pretty well thanks to three foam layers that are placed on top of pocketed coils.

Therefore, both you and your partner can enjoy undisturbed sleep even if one of you tends to sleep restlessly. What’s more, you can use the entire sleep surface without a fear of slipping off the bed thanks to excellent edge support.

In addition, the Alexander Signature Hybrid mattress has great temperature regulation, for two reasons. First, the coils improve the airflow, and second, the foam layers are infused with copper and a cooling gel. All this makes it a solid pick for hot sleepers.

This great king size mattress comes in three firmness options, so you can choose the one you like most. What’s more, Nest Bedding offers an internal split option, which is the best option for couples whose preferences differ greatly.

And don’t forget that Nest Bedding’s mattresses come with a lifetime warranty.

Leesa Original Mattress

Leesa Original Mattress
  • Amazing Pick for Hot Sleepers

  • Type: Foam

  • 100-night trial

  • 10-year warranty

  • Free shipping

  • Price: $1,299

Rating 9.6

Get the Best Deal
PROS :
  • Good spinal support

  • Excellent at isolating motion

  • Doesn’t sink too much

CONS :
  • Too firm for some sleepers

The Leesa mattress is made of three types of foam, which are designed to support and align the body in all sleeping positions. Thanks to its special foam in the top layer and memory foam in the recovery layer, this mattress is very comfortable.

We believe it’s especially good for stomach and back sleepers, who don’t enjoy too much sinkage. However, even though these two premium top layers allow for pressure relief, some side sleepers find the mattress a bit on the firm side.

The great news is that the Leesa mattress minimizes motion transfer, so couples can sleep peacefully without worrying that they’ll wake each other up if they tend to change their sleeping positions. It’s also quite breathable, especially for an all-foam mattress. Plus, the cooling foam top will keep you cool throughout the night.

Besides using quality materials and offering great comfort, Leesa is special for other reasons as well. This mattress company donates a mattress to a shelter for every ten it sells. It also plants a tree whenever it sells a mattress. It’s amazing to participate in their honorable goals.

TEMPUR-ProAdapt Mattress

TEMPUR-ProAdapt Mattress
  • Perfect for Couples

  • Free shipping

  • 90-night trial

  • 10-year warranty

  • Price: $3,699

Rating 9.9

Get the Best Deal
PROS :
  • Excellent motion isolation

  • Three firmness levels

  • Removable cover

CONS :
  • Average temperature regulation

Tempur-Pedic offers a variety of high-quality mattresses, so most sleepers can find the feel they prefer. Its most popular model is Tempur-ProAdapt, which we believe is a great choice for couples.

It’s a luxurious all-foam bed, which offers great pressure relief and spinal support in all sleeping positions. The Tempur-ProAdapt comes in three firmness levels, so depending on your sleep needs, you can opt for a soft, medium, or firm feel.

Since foam layers absorb motion pretty well, you don’t have to worry you’ll wake up your partner if you have a restless night. Usually, this is one of the most important features for couples. Also, this mattress provides decent edge support.

However, if you tend to use the entire bed surface, we recommend you get a hybrid version of this bed. In addition, the hybrid option has better temperature regulation because coils promote air circulation. Finally, this is also a great pick for heavy people since it offers ample support.

How to Pick the Right King Size Mattress

— Buyer’s Guide —

A king size mattress is a great option for anyone who has a spacious bedroom. Here’s what you need to know if you’ve decided to upgrade your shut-eye.

Comfort Level

Of course, the most important feature of any mattress is its comfort level since its main purpose is to allow you to have a good night’s sleep. And you can’t rest properly if your bed isn’t comfortable.

However, it’s really challenging to find the top mattresses according to the level of comfort they provide because this is usually a pretty subjective feel. It’s always a good idea to check out some of the king size mattress reviews for information on comfort level. 

While some people prefer very firm mattresses, others find them extremely uncomfortable since they put additional pressure on their joints, like their shoulders or hips. On the other hand, soft mattresses can offer pleasant cushioning around your pressure points. Still, for some sleepers, a soft mattress can mean waking up with back pain.

As you’ll see below, choosing the right mattress will mostly depend on your preferred sleeping position.

Sleeping Position

Regardless of its firmness level, a solid mattress needs to provide adequate support to the body and keep the spine in perfect alignment.

  • Back sleepers need a mattress that offers ample support to their shoulders, trunk, and hips. That’s why they usually benefit most from medium to firm mattresses that don’t allow for much sinkage.
  • Side sleepers usually prefer a softer bed that provides pressure relief for their shoulders and hips. They enjoy the deeper hug that most foam mattresses offer. They can also consider looking for a king size mattress topper if their mattress is too firm.
  • Stomach sleepers, like back sleepers, also need solid support for their hips since otherwise their spine may be in an unnatural position, causing them to wake up with back pain. That’s why they should look for firmer mattresses.
  • Combo sleepers need to pay attention to the sinkage level of a mattress since they don’t want to feel stuck when changing positions during the night. That’s why a soft mattress usually isn’t the best option for them.

Sleeping Preferences

Besides your preferred sleeping position, you need to think of your other sleeping preferences. For example, are you a hot sleeper? Or do you often wake up with aches and pains? Before you start looking for the best deal, consider the following, since this will help you find the perfect king size mattress for your needs.

  • People who suffer from back pain tend to like medium-firm mattresses. Also, memory foam mattresses are usually the best option for back pain since they contour around the body, not leaving any gaps.
  • Heavy people generally need an innerspring or hybrid mattress since coils provide ample support.
  • Couples need to pay special attention to edge support. If a mattress doesn’t provide adequate support at its edges, sleepers might feel like they’ll fall off the bed. However, since king size mattresses have a large sleeping area, this shouldn’t be an issue. In addition, a mattress should absorb motion effectively. This is another important feature for couples, especially if one or both of them are light sleepers.
  • Hot sleepers who tend to wake up sweaty should stay away from foam mattresses. These typically retain more body heat and don’t have good airflow.
  • Sleepers who suffer from allergies should look for mattresses made of memory foam or latex (if they’re not allergic to it, obviously).

Quality

When buying a new mattress, high quality should definitely be one of your top priorities. If you settle for one made of low-quality materials or with poor construction, you’ll quickly end up with an uncomfortable mattress. To avoid waking up with aches and pains, you need to find a mattress that will support you in the years to come.

That’s why you need to pay special attention to the materials used, the type of construction, and the number of layers. Generally, coil and hybrid mattresses tend to be more durable than foam mattresses since they don’t sag quickly. However, there’s a range of different foams, all of varying qualities and densities. High-density foam will typically provide solid support to both the mattress’s top layers and your body.

Trial Period and Return Policy

Buying a mattress online usually comes with a great perk—a trial period. Most reputable mattress brands offer a period during which you’re able to try your mattress at home and decide if it’s right for you. This is your safety cushion. If the mattress doesn’t meet your expectations, you can return it to the manufacturer at little to no cost.

When we ranked king size mattresses, we took into account whether the companies offer a sleep trial period, how long it lasts, and how simple their return procedure is.

We don’t recommend buying a mattress without testing it, so this feature greatly affected our final score. When you know that there’s a money-back guarantee, there won’t be additional pressure for you while weighing all the pros and cons.

Warranty

Checking if the manufacturer offers a warranty and what it covers is another important thing to do. Most mattresses come with a 10-year warranty regardless of their price, but it’s always recommended to carefully read the fine print to know what kind of damage is covered and under which conditions.

Price

King size mattress prices range from several hundred to several thousand dollars. While your choice will depend on your budget, we tried to assess what you’ll get for your money. Handing over a small fortune on a mattress doesn’t guarantee that you’ll get the best product. Therefore, we give our all to find the mattresses that offer good value for the money.

If you’re particularly concerned about the price, you can also take a look at our top list of the most affordable mattresses on the market.

The Benefits of a King Size Mattress

Many couples, especially those who like to cuddle throughout the night, choose a queen size mattress for themselves. While a queen mattress is 60″ wide and 80″ long, a king mattress is wider—by 16″, to be precise.

So its greatest advantage is pretty obvious—you’ll have more space to stretch out and enjoy your night’s rest. It’s great that there are so many inexpensive king size mattresses, so you don’t need to splurge on this amazing upgrade.

No matter if you sleep alone or with a partner, this extra sleeping area makes the bed more comfortable. Also, if you have a kid or a furry friend who likes to sneak into your bed, you’ll definitely appreciate the additional room you’ll get with a king size mattress.

Another benefit that comes with a king size is a sense of luxury, especially if you get a mattress with a thicker profile or opt for a pillow top mattress. This is the simplest way to add some luxury to your bedroom and make it feel like you’re in a 5-star hotel.

A King vs. California King Mattress

Both king and California king mattresses are larger than queens. While their total surface area is almost the same, they have different dimensions. 

The king mattress dimensions are 76″ x 80″. That’s why it’s perfect for couples or even parents who sleep with their child in the same bed.

A California king is 72″ x 84″. This means that it is 4″ longer than both king and queen size mattresses. When it comes to its width, it’s somewhere between a king and queen size. This makes it perfect for taller people who need extra space for their legs.

A Split King Mattress

Some people decide to place two smaller mattresses next to each other on the same base to get a split king.

You might choose to put two twin mattresses together to get the width of a king size mattress, since a twin size mattress is 38″ x 75″. However, you’ll end up with a slightly shorter bed. If you want to get the exact mattress size, you’ll have to put two twin XL mattresses together, since a twin XL is 38″ x 80″.

But why would you want to do this? Maybe you and your partner don’t have the same sleeping preferences and can’t agree on the same firmness level. This way, each of you gets a chance to choose how firm your side of the bed will be.

Besides allowing you and your partner to enjoy a unique level of comfort while in bed, a split king mattress is also the perfect solution for a king size adjustable bed. With this kind of mattress, each of you can set up the base in your preferred position.

Wrapping Up

Hopefully, our list of the top-rated king size mattresses as well our detailed guide on buying a mattress will be of great help to you. As you can see, there are a number of things you need to consider in order to find the best fit for your needs. But we hope that with our guidance, your choice will be much easier!

FAQs

How do I pick the best mattress?

Every person is different, and every sleeper’s needs are different, too. Therefore, in order to find the best mattress for you, think of your preferred sleeping position and sleeping preferences. For example, if you tend to wake up sweaty, it’s best to look for innerspring or hybrid mattresses, which are generally more breathable than foam mattresses. Also, never buy a mattress without testing it, either in a store or, even better, at home. Most online mattress brands offer a risk-free period during which you can sleep on a new mattress and decide if it’s right for you.

Which mattress is best for back pain?

Most sleepers with back pain recommend latex and memory foam mattresses. Hybrid mattresses are also a good choice because their coil system provides zoned support, while the top layer offers pressure relief.

Generally, which mattress will suit you best will depend on your body weight and sleep preferences. Just keep in mind that the bed needs to provide ample support and keep your spine in perfect alignment, while conforming to your body.

How wide is a king size bed?

A king size bed is 76″ wide and 80″ long. This means it’s 16″ wider than a queen mattress and 23″ wider than a full size mattress. However, always check the dimensions of a mattress before buying it since some manufacturers produce mattresses in non-standard sizes.

What size is a California king?

A California king mattress is 72″ wide and 84″ long. So it’s 4″ narrower than a king size mattress, but 4″ longer. In fact, it’s the longest mattress and therefore best suited to very tall people.

How big is a king size blanket?

Blanket sizes are not standardized the same way mattresses are. However, a king size blanket is generally 108″ wide and 90″ to 100″ long.

What is the best month to buy a mattress?

The time of the year may actually affect the price of a mattress. Typically, most retailers offer discounts between February and May because they are making room for new models, which usually arrive in June.

In addition, weekends around national holidays are a great time to go shopping for a mattress. President’s Day, Memorial Day, Fourth of July, Labor Day, and Black Friday are all great occasions to buy a new mattress since that’s when you’ll probably get the best deal.

What size washer do I need for a king size comforter?

A king size comforter can fit in a machine whose capacity is at least 3.8 cubic feet. However, always check the comforter’s label before machine-washing it because some delicate materials need to be hand washed.

How much does a king size mattress cost?

The prices of king size mattresses greatly vary depending on the brand, type, and materials used. They range from a few hundred to a few thousand dollars. Therefore, regardless of your budget, you can find a quality king size mattress.