The biggest bed size available is the family bed XL measuring 144 inches wide and 84 inches long. Other oversized mattresses include the Alaskan king, Alberta king, Texas king, Wyoming king, and California king.
While most assume the California king bed earns the title of biggest bed size, some manufacturers have developed even larger sizes to accommodate different sleepers’ needs.
The biggest bed size available is the oversized family bed XL at 144 inches wide and 84 inches long. The most common mattress size in America is the queen-size mattress (60 inches wide by 80 inches long), and the second most popular is the king size mattress (76 inches wide by 80 inches long). At Purple, the largest bed sizes we offer are the king and California king.
If you’re a co-sleeping family with multiple children and pets, an oversized mattress may best match your needs. With seven sizes to choose from, you can find the size that best matches your sleep situation. Follow along as we highlight the biggest bed sizes available, how to choose the right one for you, and where to buy an oversized mattress.
The biggest bed size on the market is the family bed XL amounting to 84 square feet in surface area. Family beds come in three sizes, with the largest (XL) measuring 144 inches wide by 84 inches long.
The second largest is the Alaskan king bed, which is the longest bed available. It measures 108 inches wide by 108 inches long.
For comparison, the family bed XL is the same length as a California king (72 inches wide by 84 inches long) but is twice as wide. The Alaskan king is over 30 inches wider and longer than the California king.
The family bed and other similar extra large mattresses are called oversized mattresses. An oversized mattress is any size that’s larger than a California king mattress.
The following are also classified as oversized mattresses:
Because of their size, oversized mattresses are typically made to order and are not stocked in your average mattress store. Oversized beds require extra large bedrooms and often custom-made bed frames and bedding. All of these factors also increase the price of these custom beds.
Let’s take a look at the different oversized mattress types, their dimensions, and the minimum recommended room sizes for each in the biggest bed size chart below.
Family bed (XL) | Family bed (large) | Family bed (medium) | Alaskan king | Alberta king | Texas king | Wyoming king | California king | |
Dimensions (in) | 144 x 84 | 120 x 80 | 108 x 80 | 108 x 108 | 96 x 96 | 80 x 98 | 84 x 84 | 72 x 84 |
Dimensions (cm) | 365.76 x 213.36 | 203.2 x 203.2 | 274.32 x 203.2 | 274.32 x 274.32 | 243.84 x 243.84 | 203.2 x 248.92 | 213.36 x 213.36 | 182.88 x 213.36 |
Surface Area | 12,096 sq in | 9,600 sq in | 8,640 sq in | 11,664 sq in | 9,216 sq in | 7,840 sq in | 7,056 sq in | 6,048 sq in |
Minimum Room Size (ft) | 17 x 12 | 15 x 12 | 14 x 12 | 14 x 14 | 13 x 13 | 12 x 14 | 12 x 12 | 12 x 14 |
Shape | Rectangle | Rectangle | Rectangle | Square | Square | Rectangle | Square | Rectangle |
Dimensions:
Family beds are some of the largest mattresses available, with the XL family bed taking the number one spot as the biggest bed size. While not the longest mattress available, the XL family bed is the widest mattress size. It is the same width as two California kings together — an impressive 12 feet wide. Its length matches a single California king bed — 7 feet long.
The large and medium family beds also vary in width (120 and 108 inches, respectively), but both measure 80 inches long — the same length as a queen mattress.
As the name suggests, family beds are wide enough to comfortably fit at least a family of four (and even the family dogs). They’re well suited to co-sleeping families or those who want the (many) extra feet of space.
Such an oversized bed requires an oversized bedroom to accommodate it. The average U.S. bedroom is 132 square feet, but family beds need between 168 to 204 square feet of space.
Since these mattresses are so large, some online mattress brands ship these often custom-made beds in a box. They also require a custom bed frame and special bedding.
Pros | Cons |
Comfortably fits co-sleeping families with several children and pets | Doesn’t fit in an average-size bedroom |
Comfortably fits adults with larger body types | Difficult to find mattresses and accessories of this size |
Fills oversized bedrooms | Hard to transport |
Dimensions: 108 inches wide by 108 inches long
The Alaskan king bed was aptly named after the largest state in America. At 9 feet by 9 feet, it is the most well-known oversized mattress. As the longest bed size, it offers additional legroom, making it well suited for tall sleepers. This size mattress has the same width as the medium family bed, which is equivalent to two full-size beds. The extra width offers plenty of space for smaller families that prefer to co-sleep but also like their space.
Pros | Cons |
Great for tall sleepers and adults with larger body types | Requires an oversized bedroom |
Allows small co-sleeping families room to move without disrupting each other | Hard to find |
Luxurious look | Often requires custom-made accessories |
Dimensions: 96 inches wide by 96 inches long
Another oversized mattress, the Alberta king measures 8 feet wide by 8 feet long, offering 64 square feet of room to sleep. It is 3 feet wider and 2 feet longer than a standard queen-size mattress.
This is a great option for couples and co-sleeping families who move around a lot while sleeping or for tall individuals to enjoy the extra legroom. Just make sure you have a larger bedroom (at least 13 feet by 13 feet) to accommodate it.
Pros | Cons |
Perfect for tall individuals and adults with larger body types | Least common oversized bed, making it difficult to find |
Comfortably fits co-sleeping families with one or two children | Requires made-to-order bedding accessories |
Dimensions: 80 inches wide by 98 inches long
Named after the second-largest state, the Texas king bed offers nearly 55 square feet of sleeping space. Compared to the California king, Texas king beds are 14 inches longer and 8 inches wider. In relation to the standard king, Texas kings are only 4 inches wider but a foot and a half longer. The extra legroom makes it a suitable choice for tall couples who like their personal space or enjoy sleeping with a furry friend.
Texas beds make a good fit for average-size primary bedrooms as their rectangular shape isn’t as wide as other oversized mattresses.
Pros | Cons |
Suitable for very tall sleepers (6.5 to 7 feet tall) with room at the foot of the bed for pets | Narrowest oversized mattress |
May fit into average-size or rectangular bedrooms | Better for sleeping with pets than co-sleeping with more than one child |
Dimensions: 84 inches wide by 84 inches long
The Wyoming king is the “smallest” within the oversized mattress category, but it’s still a foot wider than a California king bed and the same length. It’s also 4 inches wider than a Texas king, but offers less surface area at 49 square feet. At 84 inches long, tall sleepers can sleep peacefully in a Wyoming king bed.
Its square shape fits comfortably in the average American primary bedroom.
Pros | Cons |
Great for tall sleepers and couples looking for extra space | Co-sleeping with more than one child or an older child may feel cramped |
Fits into average-size primary bedrooms | Doesn’t work for guest rooms or small bedrooms |
Dimensions: 72 inches wide by 84 inches long
The California king, though not considered oversized, is the longest standard bed size available on the market. In comparing king vs. California king mattresses, a California king is 4 inches longer than the standard king but also 4 inches narrower. This extra length makes it a great option for tall sleepers who don’t need as much personal space.
Pros | Cons |
Room for two adults and one small child | Co-sleeping with more than one child or an older child may feel cramped |
Commonly sold and readily available | Commonly considered bigger than a king but actually offers a smaller surface area |
Fits into average-size primary bedrooms |
Deciding which size bed is right for you can be challenging, especially when considering the biggest bed sizes. Here are some things to factor into your purchase, including:
When you’ve gone through your options and are certain that an oversized bed is what you want, you’ll need to find a supplier. Oversized mattresses are far larger than standard mattresses, so you won’t find them at your typical mattress supplier.
Start your hunt by browsing mattresses online for a manufacturer specializing in oversized or custom-sized mattresses. Be sure to read through reviews and frequently asked questions to understand the company’s:
An easier and potentially more affordable solution is to buy mattresses in standard sizes and combine them into the size of an oversized bed.
For example, let’s say you already have a queen mattress, but you’d like to upgrade to a bigger bed. Instead of getting rid of your queen bed, you could get a twin XL and combine them to get one giant Texas king (98 inches by 80 inches). Similarly, you could purchase a second queen mattress to add to your existing queen to make one large family bed (120 inches by 80 inches).
Or, if you already have a California king and you want to go even wider, you can make the biggest bed size by purchasing a second California king mattress. Two California king mattresses combined create an XL family bed (144 inches by 84 inches).
These hacks may make it easier to build an oversized mattress and find bedding, but you’ll still need the proper bed frame — likely custom-made.
If your bedroom won’t fit an oversized mattress but you want to upgrade to a bigger bed size, choose a mattress from Purple in a king or California king size. Our patented GelFlex® Grid technology provides adaptive support, softness, and comfort that can help you get rejuvenating sleep and start your day refreshed.
Biggest Bed Size FAQ
The family bed XL is the widest mattress at 144 inches. This specialty size requires custom manufacturing. The widest mattress sold by most mattress retailers is the king mattress at 76 inches wide.
The longest mattress is the oversized Alaskan king at 108 inches. The California king is the longest mattress commonly available to consumers at 84 inches.
King beds are not the biggest bed size. A California king is bigger than a king in length by 4 inches. Other beds larger than a standard king include:
No, queen mattress and bed frame dimensions are not the largest available. There are nine mattress sizes larger than a queen, including:
The biggest bed size is the family bed XL. The family bed XL measures 144 by 84 inches and is bigger than an Alaskan king.