King vs. California King: Which Mattress Size Is Right for You?

Key Takeaways

• A King mattress is wider, while a California King is longer, offering nearly identical total sleeping space.
• King mattresses work best for couples who want maximum side-to-side room or share the bed with kids or pets.
• California King mattresses are ideal for taller sleepers or longer, narrower bedrooms.
• Mattress construction and fit matter more than size alone, making in-person testing especially important.

A large, luxurious mattress can be one of the best investments you can make in quality sleep, but choosing the right size isn’t always straightforward. King, California King, and other custom or oversize mattress options offer generous sleeping space. However, they are designed for different needs, with some prioritizing width for sleepers who want room to spread out, while others prioritize extra legroom.

In this guide, we’ll walk you through everything you need to know to compare a King vs. California King mattress. Since 1986, Custom Comfort Mattress has been using an individualized approach and personalized showroom fittings to help customers navigate the mattress-buying process, understanding that the right mattress size depends on more than just your height or bedroom dimensions. Mattress choice is about how you sleep, who you share your bed with, and what feels comfortable for your body. Read on to learn which king-sized mattress is right for you.

King vs. California King — Quick Size Comparison

The fundamental difference between these two mattress sizes comes down to width versus length:

Mattress Size	Dimensions (W × L)	Total Surface Area
King (Eastern King)	76″ × 80″	6,080 sq. in.
California King (Cal King)	72″ × 84″	6,048 sq. in.

In plain terms, the King is 4 inches wider and 4 inches shorter, while the California King is 4 inches longer and 4 inches narrower. Both sizes are standard U.S. mattress dimensions, meaning sheets, bed frames, and accessories are widely available for either size, and offer nearly identical total sleeping area. The difference lies entirely in shape and proportion.

There are also custom and oversize options for sleepers who need dimensions beyond the standard, whether that’s extra width, extra length, or a unique size to fit an antique frame or specialty bed – all of which Custom Comfort Mattress offers. For a complete breakdown of all mattress sizes, refer to our ultimate guide to bed size charts.

What’s the Difference Between a King and California King Mattress?

The King mattress (sometimes called an Eastern King) prioritizes width over length. At 76 inches wide, it gives each partner in a couple 38 inches of horizontal personal sleeping space, equivalent to more than a Twin XL provides for a single sleeper. This makes the King ideal for couples who want maximum side-to-side room, whether because one partner moves frequently during the night, because kids or pets join them in bed, or simply because they prefer not to feel crowded.

While many think the California King is larger overall, this mattress actually prioritizes length over width. At 84 inches long, it provides four extra inches of legroom compared to the standard King and other XL mattress sizes. For sleepers over 6 feet tall, those additional inches can mean the difference between comfortable sleep and waking up with feet hanging off the edge. The trade-off is 4 inches less width. At 72 inches wide, the California King is still spacious for couples but noticeably narrower than the standard King.

Choosing between them is really about finding the right proportions for your body, preferences, and space. When properly fitted and constructed of high-quality materials, like a Custom Comfort Mattress, either size can provide years of lasting comfort and quality sleep.

Who Should Choose a King Mattress?

A traditional King mattress is an ideal choice for couples who value personal sleeping space. That extra 4 inches of width compared to a California King translates to a meaningful sleep area, especially for partners with different sleep schedules, those who toss and turn, or sleepers who simply prefer their own space at night.

Families with young children or pets can also benefit from the King’s width. If weekend mornings involve kids climbing into bed or a dog sleeping between you, the King’s 76-inch width accommodates the crowd more comfortably than the narrower California King. And even most taller sleepers find the 80” length adequate as long as the mattress provides proper support and comfort.

From a room layout perspective, the King works best in large square bedrooms or those that are wider than they are long. A room should measure at least 12 by 12 feet to provide comfortable clearance for a King mattress, nightstands, and walking space.

Who Should Choose a California King Mattress?

The California King mattress is designed for sleepers who need extra length. If you’re over 6 feet tall and have ever woken up with your feet dangling off the mattress, you understand the value of those additional 4 inches. The California King’s 84-inch length comfortably accommodates taller frames, allowing you to stretch out fully without compromising sleep position.

For couples where one or both partners are tall, the California King provides meaningful comfort advantages. Proper leg support and the ability to sleep in a natural position without curling up or angling diagonally across the mattress contribute to better spinal alignment and more restful sleep. The 72-inch width still offers 36 inches per person, typically plenty of space for two, and just slightly less than the King’s 38 inches per side.

The California King also suits longer, narrower bedrooms better than the standard King. Its slimmer profile fits more naturally in rooms that are deeper than they are wide, leaving adequate clearance on the sides for nightstands and movement. If your bedroom is at least 11 feet wide and 13 feet long, the California King’s proportions may work better than forcing a wider King into the space.

Bedroom Size and Layout Considerations

Before choosing between a King and California King, measure your bedroom carefully. The mattress dimensions are just one piece of the puzzle. You’ll also need to factor in clearance for walking, making the bed, and any furniture you want alongside it, as well as window and door placement.

For a King mattress, a room of at least 12 by 12 feet provides roughly 24 to 30 inches of clearance on each side for nightstands and walking space, plus room at the foot of the bed for a bench or clear pathway. 

For a California King, the bed’s longer, narrower shape works better in rooms that extend lengthwise. A room at least 11 feet wide by 13 feet long accommodates the bed’s extra length while providing comfortable side clearance.

In smaller rooms, any king-sized bed can feel overwhelming and make the space feel cramped.

Tip: Don’t forget to consider delivery logistics. Measure doorways, hallways, staircases, and any tight corners between your home’s entrance and the bedroom. Most King and California King mattresses can navigate standard doorways (typically 32 to 36 inches wide) when angled, but older homes with narrow passages may present challenges. If access is a concern, ask about delivery options or consider mattresses that compress for easier maneuvering.

King vs. California King for Couples

For couples, mattress size is only part of the comfort equation. How you experience shared sleep depends significantly on mattress construction, motion isolation, and whether the mattress accommodates different comfort preferences. 

Motion transfer, or how much you feel your partner’s movements, varies more by mattress construction than by size. Quality innerspring systems with individually wrapped coils reduce motion transfer by allowing each coil to respond independently. While foam is superior at minimizing motion transfer, natural latex also isolates movement well while providing responsive support. 

For couples with different firmness preferences, consider a split mattress configuration. This approach uses two separate mattress halves, customized to the individual sleeper’s comfort level, and places them together on a shared frame or adjustable base. When properly fitted, the split feels seamless at the center while delivering personalized comfort on each side.

Both King and California King sizes work well in split configurations, though the King’s wider dimensions mean each half provides slightly more individual space. If independent comfort zones or firmness levels are a priority, discuss split options with a sleep specialist or during your showroom fitting.

Mattress Feel Matters More Than Size

Whether King or California King proportions better fit your needs, the more important decision is how the mattress actually feels. Size gets you the right footprint; construction and materials determine whether you sleep well on it.

Support and pressure relief work together to keep your spine aligned while cushioning your shoulders, hips, and other pressure points. The right balance depends on your body weight, sleep position, and personal preferences far more than whether your mattress is 76 or 72 inches wide. A too-firm mattress creates pressure points regardless of size, while a too-soft one allows your body to sink out of alignment.

Materials also impact both comfort and durability. Natural latex offers responsive pressure relief and exceptional longevity. Organic cotton and wool regulate temperature and wick moisture, keeping you comfortable through the night. Quality innerspring systems provide foundational support while promoting airflow. Some synthetic foams can trap heat and may break down more quickly over time, losing their supportive properties within a few years.

At Custom Comfort Mattress, we handcraft every mattress with natural materials and a double-sided design to ensure long-lasting comfort. A dual-sided mattress that you can flip and rotate distributes wear evenly across both sleeping surfaces, extending the lifespan compared to single-sided designs. When investing in a King or California King, construction quality is what separates a mattress that supports great sleep for 15 years from one that sags and softens after 5.

Adjustable Bases and Split Options

Both King and California King mattresses are compatible with adjustable bed bases, which allow you to raise your head, feet, or both for customized positioning. Adjustable bases can help with acid reflux, snoring, circulation, and general comfort, not to mention the flexibility they offer for reading or watching television in an elevated position.

For couples, split adjustable bases take customization to the next level. A split King or split California King uses two separate bases side by side, allowing each partner to adjust their position independently. One partner can elevate their head for reading while the other lies flat for sleep, without compromising individual comfort.

Pairing a split adjustable base with a split mattress configuration gives each partner complete control over both mattress feel and sleep position. This combination works particularly well for couples with significantly different preferences or health needs that benefit from elevated positioning.

How to Decide: King or California King?

Choosing between a King and California King mattress comes down to height, room dimensions, and how you sleep.

Height: If either you or your partner is over 6 feet, the California King’s extra 4 inches of length can provide noticeable comfort. For sleepers under that height or even 6’ 2”, the standard King’s 80 inches is typically sufficient.

Bedroom shape: Wider rooms suit the King’s 76-inch width; longer, narrower rooms accommodate the California King’s 84-inch length more gracefully.

Sleep style: Couples who prioritize side-to-side space, share with children or pets, or move frequently during sleep often prefer the King. Taller sleepers or those who scoot down in the bed to sleep benefit from the California King.

Accessories and options: While the traditional King might have a slight edge, bedding and accessory options are readily available for both King and California King mattresses.

If none of these factors point clearly in one direction, either bed size can deliver spacious, comfortable sleep when paired with a quality mattress that correctly supports your body, which is why an in-person trial and personalized fitting are so critical.

Of course, if standard dimensions don’t quite fit your needs, Custom Comfort Mattress can build a custom mattress to your exact specifications.

Experience the Difference In Person

Even when thoroughly versed in the differences between a King and California King mattress, comparing them on paper only takes you so far. The best way to understand how a mattress fits your body is to lie down on both sizes in person and feel the difference for yourself.

At a Custom Comfort Mattress showroom, you can test King and California King mattresses side by side with guidance from sleep specialists who evaluate proper fit, feel preferences, bedroom space, and sleep style to match you with the right sleep solution for your needs. Every mattress we build is handcrafted in our Southern California factory and designed for lasting comfort – not planned obsolescence – using natural materials and traditional double-sided construction. Visit a Custom Comfort Mattress showroom to find the perfect King or California King for your best night’s sleep.

FAQs

Is a California King bigger than a King mattress?

A California King is not larger overall than a standard King. Both sizes offer nearly the same total surface area, but the King is wider while the California King is longer, making the difference one of proportion rather than size.

Which mattress size is better for couples?

Most couples prefer a standard King mattress because its extra width provides more personal space for each sleeper. However, taller couples may benefit from the California King’s added length if legroom is a priority.

Will a King or California King fit in my bedroom?

A King mattress works best in rooms at least 12 by 12 feet, while a California King fits better in rooms that are longer than they are wide. Measuring your space, doorways, and furniture clearance is essential before choosing either size.

Can Custom Comfort make a custom or oversized King mattress?

Yes, Custom Comfort Mattress offers custom and oversize mattress options for sleepers who need additional width, length, or nonstandard dimensions. Custom sizing is especially helpful for taller sleepers, specialty bed frames, or unique room layouts.