King vs. California King: What’s the Difference?

Many people assume California king mattresses are bigger than standard king beds—but that’s not necessarily the case. While California king mattresses have more length, they’re four inches narrower than a regular king.

A king mattress, also called the Eastern king bed, measures 76 inches by 80 inches, with a total surface area of 6080 square inches. A California king mattress, also called Western King, measures 72 inches by 84 inches, with a total surface area of 6048.

King vs. California King Mattress

King Size Overview

King Size Mattress Dimensions: 76 inches x 80 inches = 6080 square inches

• Also called “Eastern King”
• Pros: Extra width is great for couples, fits easily in most master bedrooms
• Cons: Heavy and difficult to move, too large for bedrooms smaller than 12 feet by 12 feet

As the largest mattress size, a king mattress is the bed of choice for anyone seeking more personal space for better sleep. It’s excellent for couples who can’t sleep too close without feeling overheated or cramped, but who still want the proximity of their partner.

However, a king mattress isn’t without its drawbacks. Moving the mattress can be a challenge, whether it’s just to change the sheets or as a more-involved process of moving house. The large size also means a king bed costs more than smaller mattresses, as do corresponding king size accessories.

Types of King Mattresses

1. Standard King (Eastern King)

The Standard King, also known as the Eastern King, measures 76 inches wide and 80 inches long, making it the widest of all standard mattress sizes. It’s a popular choice for couples who value personal space while sleeping or for families who co-sleep with children or pets. 

This mattress is ideal for larger, square-shaped bedrooms (12′ x 12′ or more), where its broad dimensions won’t overwhelm the space. It gives each sleeper roughly the same width as a Twin XL, offering excellent room to move around without disturbing your partner. Most bedding brands offer a wide selection of frames, sheets, and accessories in this size, making it both convenient and practical.

2. Split King

A Split King mattress consists of two Twin XL mattresses (38″ x 80″) placed side by side to form the dimensions of a Standard King. This setup is especially beneficial for couples with different sleep preferences, such as varying mattress firmness or sleeping positions. It’s also the go-to choice for adjustable bed bases, allowing each person to raise or lower their side independently. 

Another major advantage is ease of transportation—each Twin XL section is easier to carry through narrow stairways and door frames. While you’ll need special Split King bedding, many brands now offer bundled sheet sets and mattress protectors specifically designed for this configuration.

3. Oversized King Mattresses (Alaskan, Texas, and Wyoming King)

If a regular King mattress isn’t roomy enough, oversized King options might be your answer. These mattresses are custom-sized and cater to families who co-sleep or sleepers who want maximum luxury.

• The Alaskan King is the largest, measuring a massive 108″ x 108″—that’s nine feet in both directions. It can accommodate two adults, children, and even pets with room to spare.
• The Texas King offers extra legroom with dimensions of 80″ x 98″, ideal for tall sleepers and large rectangular rooms.
• The Wyoming King is a balanced option at 84″ x 84″, providing both width and length above the standard King.

These sizes are not commonly stocked in retail stores and often require custom ordering. While they offer unmatched space, finding bedding, frames, and accessories can be expensive and more limited.

SEE ALSO: Best King Size Mattress

The AS3 from Amerisleep is our top recommendation for two people who want to harmoniously share a king size mattress. The trouble with picking out a king bed, or for that matter a queen bed, for couples is that two individuals rarely have 100 percent compatible sleeping styles. For example, one may be a side sleeper, the other a back sleeper.

If they want to share a mattress, then, they need one with a versatile feel that contours to the body in most positions. A medium feel memory foam mattress like the AS3, carefully constructed to feel comfortable to sleepers with different preferences and body types, is a logical choice.

The AS3 is backed by a 100-night sleep trial and a 20-year warranty. Couples who are more interested in a buoyant mattress with a springy feel might want to consider the AS3 Hybrid.

How It Feels?

As we noted, the AS3 has a medium feel surface designed to promote near-universal comfort. The plant-based memory foam feels cool thanks to an airy structure. However, the advanced open-cell design doesn’t make the bed less supportive by providing space for airflow. Indeed, the AS3 reacts faster to movement than the average memory foam mattress, regaining its shape within seconds.

Inside the Mattress

What surrounds the AS3 mattress is a soft, cooling Refresh fabric cover. This cover fabric is woven to reduce the surface temperature by as much as 7 degrees Fahrenheit, a cooldown that helps individuals fall asleep faster and sleep deeper and longer.

Refresh also relies on minerals to transform body heat into infrared energy, which can penetrate the body and boost blood circulation for improved restoration.

The first layer of the AS3 is Bio-Pur® foam. What separates this memory foam from traditional memory foam is its partly plant-based formula, with certain petrochemicals receiving more natural substitutions. This recipe creates a responsive and breathable cushion that adapts to changes in body positions within seconds.

The second foam layer is the Affinity foam with HIVE® technology. Hexagonal cutouts make up the five support zones implemented in this layer, ensuring the bed feels softer and firmer at alternating points under the body.

The third and final layer is Bio-Core® foam, a material used to establish a durable mattress that won’t sag. This is especially helpful for couples, as lower-quality king and queen mattresses tend to sink in the middle after extended use.

SEE ALSO: Most Comfortable Mattresses – Reviews and Buyer’s Guide 

California King Size Overview

California King Size Mattress Dimensions: 72 inches x 84 inches = 6048 square inches

• Also called “Western King”
• Pros: Offers four extra inches of legroom, can comfortably accommodate sleepers over 6 feet tall
• Cons: Accessories are costly and harder to find, may not be wide enough for parents to co-sleep with their children

As the name suggests, the California king mattress was conceived of in California as an alternative to the popular king size mattress. The added length ensures that tall sleepers don’t have to deal with their legs hanging over the ends.

Some sleepers mistakenly believe a California king size mattress is more luxurious than a king mattress, but it is not. What makes a luxury mattress usually comes down more to high-quality materials than mattress size along.

Types of California King Mattresses

1. Standard California King

The California King mattress measures 72 inches wide and 84 inches long, making it 4 inches narrower but 4 inches longer than the Standard King. It’s a top choice for tall individuals who need more legroom, and it fits better in narrow or elongated bedrooms where a wider bed might feel too bulky. 

While it offers slightly less surface area than a King, many couples find the extra length well worth the trade-off—especially if they sleep with pets at the foot of the bed. The elongated profile also lends a sleek, elegant look to modern bedrooms. However, accessories like sheets and bed frames are less widely available, so you may need to search a bit harder or pay more.

2. Split California King

A Split California King is made of two separate mattresses, each measuring 36 inches wide by 84 inches long, placed side by side. Like the Split King, this setup is ideal for couples with individual comfort needs or those who use adjustable bases. 

Each partner can control their side of the bed—raising the head or foot without affecting the other side. The extra length is still ideal for tall sleepers, and the split design offers an excellent balance of comfort and independence. However, just like its standard counterpart, Split California King bedding and accessories are harder to find and often more expensive, so be prepared to invest a little more effort in sourcing compatible products.

SEE ALSO: Softest Mattress in a Box

The Zoma Hybrid is our top recommendation when it comes to a bed for tall sleepers that sleep hot. The hybrid has a simple design that packs a lot of value, keeping a king size hybrid mattress extremely affordable for most sleepers.

Purchase of a Zoma Hybrid includes a 100-night sleep trial and a 10-year warranty.

How Lying Down Feels?

When stretching out on a California king size Zoma Hybrid, what might first strike a sleeper is how pleasantly soft the bed feels. It’s rated a medium, so the mattress yields well to pressure while still feeling supportive under the body.

Inside The Mattress

Four layers make up the Zoma Hybrid, all of which are encased in an airy, plush AirCloth cover. As the name suggests, AirCloth was woven to promote airflow through the mattress, increasing heat dispersion.

The top layer is gel-infused memory foam, a pressure-relieving material that moves heat swiftly away from the body. The gels infused inside the first layer also ensure the mattress not only feels cool when lying down but stays cool throughout the night.

The middle layer is a buoyant transition foam known as Reactiv™, named for its flexibility and responsiveness. The material possesses a lift that keeps sleepers from bowing too far into the mattress, limiting the chances of misalignment and making movements easier.

The main support core is pocketed coils, with every coil wrapped to keep movements from bouncing across the mattress surface. The coils wrapping around the side are thicker than the rest, establishing firm edge support. These coils rest on a supportive foam base to ensure they stand strong after years of use.

SEE ALSO: Most Durable Mattresses

Should I Buy a King or a California King Size Mattress?

How do you determine the best mattress size for you? Below we breakdown some key factors to consider before purchasing your new bed.

1. Cost

Although king and California king mattresses are typically around the same price, the bedding and accessories for a Cal king can be more costly and harder to find. Items such as bed frames, box springs, comforters, bedsheets, adjustable beds, and mattress protectors may cost more with a Cal king size bed.

Since California king mattresses are not as popular as regular kings, these items are also not as readily available.

2. Room Size

In the US, a standard size bedroom will measure 11 feet by 12 feet (132 square feet). A master bedroom will offer more space; these rooms measure 14 feet by 16 feet (309 square feet).

When considering a king or a California king size mattress, you should be sure you have adequate space to accommodate a mattress of this size. At least 2 feet of space on all 3 sides of the bed will give you enough space to move around the bed comfortably. It will also keep the room from feeling overcrowded.

If your room measures more narrow, a Cal King might be the best bet for you. However, if your bedroom is wider, a standard king size mattress should work well.

3. Your Height

A California king bed is great for taller people–especially those over 6 feet. This extra length can give you more legroom and ensure that your feet never hang off the end of the bed. Based on your personal preferences, this may help you feel more supported during sleep. If you have the room to accommodate this size bed, it is worth it to opt for the Cal king if you are on the taller side.

4. Couples

Although a queen mattress is a popular choice for many couples, a king or a California king mattress offers even more sleeping space. Maybe your partner frequently tosses and turns during the night, or you have kids who like to climb into bed with you–a bigger mattress will help you stay comfortable.

When looking for a mattress for couples, you can’t go wrong with either a king or California king. If you and your partner prefer to sleep closer together, but also like extra legroom, a Cal king is your best option. If you prefer more space between you and your partner, you will want to go with the wider, standard king size bed.

5. Sleeping Position and Sleep Habits

Your sleeping style and nightly habits should not be overlooked when choosing between a King and California King. Side sleepers tend to spread out more during the night, requiring extra space to extend their legs and arms comfortably. In this case, the wider surface of a King mattress (76 inches across) offers more elbow room and can prevent you from feeling restricted.

On the other hand, back and stomach sleepers often remain more centered on the bed, and if you’re particularly tall, the extra 4 inches of length on a California King (84 inches long) can keep your feet from dangling off the edge. If you or your partner tend to toss and turn or sleep diagonally, the dimensions of your bed can significantly impact sleep quality and nighttime disturbances.

6. Pets and Children in Bed

If you’re a pet parent or a family that loves weekend snuggles with the kids, mattress size becomes even more crucial. A standard King mattress, being the widest mattress size available, offers a generous sleeping surface for multiple sleepers—whether it’s two adults, a dog, and a child, or all of the above. This makes it ideal for families who co-sleep or experience middle-of-the-night visits from little ones. 

However, if your pets tend to sleep at the foot of the bed, you may appreciate the California King’s longer frame, which offers more vertical space so that your feet aren’t crowded. This extra legroom can make a real difference when sharing space, helping everyone sleep more comfortably.

7. Ease of Moving and Setup

When choosing a large mattress, logistics matter—especially if you live in an apartment building, have tight stairwells, or anticipate moving in the near future. While both King and California King mattresses are bulky and typically require two people to move, the extra length of a California King can make it trickier to navigate through narrow doorways or corners. 

It’s also harder to find split models and adjustable bases for Cal King sizes compared to regular Kings. If you live in a home with limited access points or plan to move frequently, a standard King may be easier to transport and reassemble, offering more convenience in the long run.

8. Aesthetics and Room Layout

Beyond function, the visual layout of your bedroom can also influence which mattress size works best. The wider frame of a King mattress fills horizontal space and often creates a more grounded, balanced appearance in large square or wide master bedrooms. This can make the room feel more symmetrical and intentional. 

In contrast, if your bedroom is long and narrow, a California King can elongate the space visually, complementing the room’s shape while maintaining a sleek, modern look. Think of your mattress as part of your room’s overall design—its size and proportion should align with the room’s structure and the way you’ve arranged your furniture.

9. Mattress Availability and Trial Periods

Although King and California King mattresses are considered standard sizes, not all mattress brands offer the same selection across both sizes. If you’re considering a specialty mattress—such as one with hybrid coils, advanced cooling technology, or zoned pressure relief—it’s important to check whether the California King is available. 

Some brands also limit their trial periods, return policies, or delivery options for less common sizes like Cal King. In such cases, a standard King may offer more flexibility, wider availability, and better customer support. You’ll also likely find a greater variety of compatible bed frames, adjustable bases, and accessories in the King size, which can simplify the buying process.

Which One Is Right for You?

• Choose a King if: You value more elbow room, share your bed with a partner (or children/pets), and have a spacious, square-shaped bedroom.

Choose a California King if: You’re tall, want more legroom, or have a narrower, elongated room.

Mattress Sizes

Saving on King Mattresses

As one of the bigger sizes, king mattresses can be a hefty investment. But you can save greatly by shopping one of the year’s big sales:

• Best MLK Day Mattress Sales
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• Best Memorial Day Mattress Sales
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Frequently Asked Questions

What is a split king mattress?

A split king is simply two twin XL beds placed side by side. A split king is a good option for couples who have different firmness preferences. You each decide the perfect firmness for you, then the two twins are fitted together to create one king-size bed. A split king mattress with an adjustable base allows couples to individually raise or lower the head and foot area on their side of the bed.

Can I have a king or a California king size mattress delivered?

Yes, most mattress in a box brands will ship their king and California king size mattresses directly to your door. You can also find plenty of mattress options in these sizes on Amazon. You may even be able to add on white glove delivery, where the delivery team sets up your new mattress and hauls away your old one.

How do king and California king beds compare to other mattress sizes?

California king and king size beds are larger than any other bed size. Queen size beds measure 60 inches by 80 inches, while full size mattresses measure 54 inches by 75 inches. However, there are non-standard sizes that are larger than king and California king mattresses, such as the Alaska king.

Will king sheets fit a California king mattress?

No. Unfortunately, king sheets will not fit a California king size mattress. A fitted sheet made for a king mattress will not be long enough to cover a Cal king.

What is the point of a California king bed?

A California king mattress is primarily marketed toward tall people, particularly those over 6 feet. Such a person may feel cramped on a smaller mattress, even a standard king mattress. The extra 4 inches ensure they aren’t sleeping with their feet dangling over the edge.

Is it Worth it to Buy a King or a California King?

The factors outlined above can help you determine whether or not a king or a California king is right for you. Ultimately, unless you are taller than average (6 feet and up), a regular king mattress will likely feel roomy enough for you.