King Size Mattresses – Size Guide and Measurements Chart

Besides having a royal name, a king size mattress is perhaps the most ideal size you can get for a mattress as a couple. It affords you and your partner a fair bit more space than a regular queen, and yet it does not necessarily cost a lot more. The queen mattress might be the best selling in the market since it has a larger audience, but I have no doubt that a king size mattress is the best option for couples.

In this post, you shall learn more about the dimensions of a king size mattress, the types available, as well as a few fun (maybe useless?) facts about them.

Let’s jump right in.

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Dimensions of a King Size Mattress

A king size mattress can comfortably sleep 2 persons, but what exactly are its dimensions? Find that out here:

Imperial measurements of a King Size Mattress

King size mattress in inches

A king size mattress measures 76 inches by 80 inches (76″x80″). That is a surface area of 6,080 square inches.

King size mattress in feet

A king size mattress measures 6.3 feet by 6.7 feet (6.3’x6.7′). That is a surface area of 42.21 square feet.

Metric measurements of a King Size Mattress

King size mattress n centimeters

A king size mattress measures 193 centimeters by 203 centimeters (193cm x 203cm). That is a surface area of 39,179 square centimeters.

King size mattress in meters

A king size mattress measures 1.93 meters by 2.03 meters (1.93m X 2.03m). That is a surface area of 3.9179 square meters.

King Size Mattress Dimensions Chart

King Mattress Size Chart

How big is a king size mattress in the USA?

Take note though that these dimensions are typical for the USA only. In fact, there might be very slight variations from one manufacturer to another, but the dimensions described above are most commonly used.

Different countries have different practices and culture, so do not treat this as representative of mattress sizes in countries besides the United States.

Thickness/Depth of a King Sized Mattress

How thick are most king size mattresses? This is one dimension that is not standard at all compared to its width and length.

King sized mattresses can range from 5 inches all the way to 20 inches, which translates to 12.7 centimeters to 50.8 centimeters.

This is due to the way king size mattresses are made and the purpose it is trying to fulfill.

Manufacturers produce mattresses that cater to different levels of comfort, quality, budget, and support level.

That said, most consumers are looking for mattresses that range from 10 to 14 inches.

Are thicker mattresses better?

It is commonly accepted that mattresses that are at least 10 inches thick provide superior comfort and support. For side sleepers, you might look at a mattress between 12 to 14 inches thick as that extra depth can provide additional support and comfort to your joints.

Additional information about the King Size Mattress

I thought it might be useful to add on some extra information about the king size mattress which some people might not know.

Did you know that there are actually 2 versions of king size mattress in the United States?

Yes! In the west coast, they are known as California King Size Mattress, which on the other coast, it is better known as the Eastern King Mattress! They key difference between the 2 is in the dimensions.

The California King Mattress has a measurement of 72 inches by 84 inches in length. That gives it a surface area of 6,048 sq. in, just a smidge smaller than the regular king size mattress we are discussing in this post.

Maybe the people over on the west coast are taller are slimmer? Just my wild guess.

Another cool fact is that the King Size mattress is actually the same as pushing 2 Twin XL mattresses together!

So if you want to do up a guest room and provide options for couples or individuals, two twin XLs will be an excellent choice. Just push them apart when you have 2 friends staying over or push them together when a couple is in.

I think this is also great if you rent your apartment or room out for Airbnbs!

Frequently Asked Questions (FAQ)

How many meters is a king size bed

In meters, a king size bed measures 1.93 meters across (width) and 2.03 meters in length.

How many sq ft is a king size bed?

A king size bed has a surface area of 42.21 sq. ft. This is derived from a width of 6.3ft and a length of 6.7ft.

Is a king size mattress perfectly square?

No, a king size mattress is not square, although it is very close to one.

What is the depth of a king size mattress?

While the width and length of a king size mattress are usually 76 inches by 80 inches, its depth or thickness can range from 5 inches to 20 inches. This is dependent on the materials used by the individual manufacturers.

Conclusion: King Size Mattress Dimensions

Now that you know the dimensions of a king size mattress, check out how you should go about choosing the right mattress! Buying a mattress is a big investment and a long term decision, so you want to be sure you get it right.

Happy mattress shopping!

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Emma Taylor

Emma Taylor is the Chief Editor at Wallccessories and writes regularly about topics surrounding home decor. Her family has moved several times over the years due to her husband's job requirements, and thanks to that, she has had many opportunities to dabble in designing and decorating real cozy homes.