If you’re shopping for a new bed, one of the most common questions is, how wide is a king mattress? Knowing the exact dimensions is crucial for planning your bedroom layout and ensuring a comfortable night’s sleep. This guide will give you all the details you need, from standard sizes to practical buying tips.
Let’s get straight to the point. A standard king-size mattress in the United States is 76 inches wide. That’s the same as 6 feet and 4 inches. In metric terms, it’s about 193 centimeters wide. This width is designed to give two adults plenty of personal space.
But there’s more than one type of king mattress. The length is typically 80 inches, but the width can vary depending on the specific style you choose. It’s important to know these differences before you make a purchase.
How Wide Is King Mattress
As mentioned, the standard or “Eastern King” mattress is 76 inches wide. This is the most common king size found across the country. It offers a balanced proportion for most master bedrooms.
However, you might also encounter a “California King.” This version is longer but narrower. A Cal King is 72 inches wide (that’s 4 inches narrower than a standard king) but 84 inches long. It’s a great choice for taller individuals who need the extra legroom.
Detailed King Mattress Dimensions
To make the best choice, you need to look beyond just the width. Here’s a detailed breakdown of common king-size dimensions:
- Standard King (Eastern King): 76″ W x 80″ L (193 cm x 203 cm).
- California King: 72″ W x 84″ L (183 cm x 213 cm).
- Split King: Two separate mattresses, each 38″ W x 80″ L. Together, they equal a standard king’s 76″ width.
There are also less common variations, like the “Wyoming King” or “Texas King,” which are even larger. These are specialty sizes and not widely available from all retailers.
Why the Width Matters So Much
The width of your mattress directly impacts your sleep quality. For couples, a 76-inch width means each person gets about 38 inches of personal space. That’s equivalent to a twin-size bed’s width for each sleeper.
This space helps minimize sleep disturbances. When one person moves or gets up, the other is less likely to be jostled. It’s a simple way to improve sleep for both people sharing the bed.
Measuring Your Room for a King Bed
Before you buy, you must measure your bedroom. A king mattress is large, and you need room to move around it. Here’s a step-by-step guide:
- Measure the room’s length and width: Use a tape measure and note the dimensions.
- Account for other furniture: Remember to leave space for nightstands, dressers, and a pathway. Aim for at least 2 to 3 feet of walking space on each side and at the foot of the bed.
- Consider doorways and hallways: Don’t forget to measure the path the mattress will take to get into the room. Check stairwells and tight corners too.
A good rule of thumb is that your bedroom should be at least 12 feet by 12 feet to comfortably accommodate a standard king bed set. Smaller rooms can feel cramped with a bed this size.
King Size vs. Other Mattress Sizes
Comparing sizes helps put the king’s width into perspective. Let’s look at how it stacks up against other common options.
- Queen Mattress: 60″ W x 80″ L. A king is a full 16 inches wider than a queen, offering significantly more space for couples.
- Full Mattress: 54″ W x 75″ L. A king is 22 inches wider, making a full size much too small for most couples.
- California King: As noted, it’s narrower (72″) but longer (84″) than a standard king.
The extra width of a standard king is it’s main advantage for couples who want space. A queen might fit in a smaller room, but the sleeping experience is noticeably different.
Bed Frames and Foundations
The mattress width isn’t the only measurement. The bed frame or foundation will add to the overall footprint. Most king-size bed frames add 2 to 5 inches per side in width.
Always check the total dimensions of the bed frame you plan to use. A platform bed might have a side rail that extends beyond the mattress. This is important for your room layout planning.
Choosing the Right King Size for You
Deciding between a Standard King and a California King depends on your needs. Ask yourself these questions:
- Who is sleeping on the bed? Is it for two adults, or do pets or children also join?
- How tall are the sleepers? Anyone over 6 feet 4 inches might appreciate the extra length of a Cal King.
- What is the shape of your bedroom? A long, narrow room might suit a Cal King, while a wider room fits a Standard King better.
Also, think about bedding costs. California King sheets and comforters are often less common and can be more expensive than Standard King bedding.
Special Considerations: Split Kings
A Split King is two separate XL Twin mattresses (38″ x 80″ each) placed side-by-side. They are often used with adjustable bed bases.
This setup is perfect for couples with different firmness preferences or sleep positions. One side can be raised for reading while the other remains flat. Remember, you’ll need two sets of XL Twin sheets, not one king-size set.
Shopping Tips for Your King Mattress
When you’re ready to shop, keep these pointers in mind to avoid common mistakes.
- Test it in person if possible: Lie down on the mattress for at least 10-15 minutes. Don’t be shy about testing it in your typical sleep position.
- Check the return policy and warranty: Understand the trial period details. Some companies offer a 100-night trial, which is very helpful.
- Consider delivery and setup: Ask about old mattress removal services. Know exactly how the new mattress will be delivered, especially if you live in a walk-up building.
Also, pay attention to the mattress height or profile. A very thick mattress might require deep-pocket sheets, which is an extra cost to factor in.
Maintaining Your King Mattress
To protect your investment, proper care is essential. A king mattress is a big purchase, and you want it to last.
- Use a mattress protector from day one. This guards against spills, stains, and allergens.
- Rotate the mattress head-to-foot every 3-6 months for the first few years. This prevents uneven wear. Some models only need rotating, not flipping.
- Support it with a proper foundation. A saggy or broken box spring can void your mattress warranty and cause it to wear out faster.
Following the manufacturer’s care instructions is the best way to ensure you get the full lifespan from your mattress, which is typically 7-10 years.
Common Pitfalls to Avoid
Even with all the right information, people make errors. Here are a few frequent ones:
- Not measuring the entire path of delivery: The mattress might fit in the room, but can it get around the tight corner in your hallway?
- Forgetting about ceiling height: If you have a low ceiling or a ceiling fan, a tall canopy bed or thick mattress might be a problem.
- Ignoring partner needs: If you share the bed, both people should be involved in the testing and decision process. Comfort is subjective.
Another pitfall is not budgeting for all the associated costs. Remember to include the price of a new frame, foundation, and bedding in your overall budget.
The Impact of Mattress Type on Feel
The width is fixed, but the type of mattress changes how spacious it feels. Memory foam, for example, can reduce motion transfer better than some springs models.
This means even though the physical width is the same, you might feel less movement from your partner on a foam mattress. Hybrid mattresses offer a blend of support and motion isolation, which many couples find ideal.
FAQ Section
How wide is a king size bed in feet?
A standard king size bed is 6 feet 4 inches wide. A California king is 6 feet even wide.
Is a king mattress wider than a queen?
Yes, significantly. A king mattress is 76 inches wide, while a queen is 60 inches wide. That’s a 16-inch difference.
What are the dimensions of a king mattress in CM?
A standard king mattress is approximately 193 cm wide by 203 cm long. A California king is about 183 cm wide by 213 cm long.
Can a king mattress fit in a 10×10 room?
It can physically fit, but it will likely feel very cramped. A 10×10 room leaves little space for other furniture or walking room. A queen is usually a better fit for a room that size.
What is the widest king mattress available?
Standard sizes top out at 76 inches for an Eastern King. However, custom or specialty “oversized” kings, like an Alaskan King, can be over 9 feet wide, but these are not standard and require custom bedding.
Do two twins make a king?
Not exactly. Two standard twin mattresses (38″ x 75″ each) make a “Double Twin” that is 76″ wide but only 75″ long, shorter than a king. Two XL Twin mattresses (38″ x 80″ each) do make a standard Split King size.
How much wider is a king than a full?
A king mattress is 22 inches wider than a full-size mattress. A full is 54 inches wide, making a king much more suitable for two adults.
Final Thoughts on Choosing Your King
Understanding the answer to “how wide is a king mattress” is the first step in a successful purchase. The 76-inch width of a standard king provides generous space for couples, but always verify if a California King or Split King might better suit your specific situation.
Take your time, measure carefully, and consider both partners needs. A mattress is a long-term investment in your health and well-being. Getting the right size is a fundamental part of ensuring you get the best sleep possible for years to come. With the right planning, your new king mattress will be a perfect fit for your bedroom and your sleep habits.