Eachnight may earn commissions for products you purchase through our links. Our articles and reviews include affiliate links and advertisements, including amerisleep advertising. Learn more Updated October 11, 2021Looking for a new mattress? Consider a king size. A king size mattress is large and spacious, providing plenty of room for you and your sleep partner. You and your partner can enjoy your personal space. Before buying a king bed, take a look at how the king size bed compared to other mattress sizes and why it’s the best fit for you.Dimensions of a King Size BedKing size bed dimensions are 76 inches wide and 80 inches tall. The mattress height depends on the brand, but height generally ranges from 8 inches to 14 inches. These dimensions give you and your sleep partner lots of room to spread out. King size mattresses are also the perfect fit for a master bedroom.King Size Bed Compared to Other Mattress SizesKing size mattresses are one of the largest standard sizes available, and the most popular bed size for couples. A king bed gives you and your sleep partner 38 inches of personal space, so neither of you will feel crowded or worry about bumping into each other.Keep in mind that a king size is harder to move because they’re large and bulky—they may not fit inside bedrooms smaller than 13 feet by 13 feet. Also, king beds are more expensive than other mattress sizes—manufacturers use more materials. If you’re single or on a tight budget, smaller mattress sizes may be better options, including twin, twin XL, full, and queen.Another size you may want to consider is the California king. California king mattresses usually cost the same as a king size, but Cal kings are a better fit for taller couples, since they’re longer and provide more leg room.Mattress SizeDimensionsTwin38 inches by 75 inchesTwin XL38 inches by 80 inchesFull54 inches by 75 inchesQueen60 inches by 80 inchesKing76 inches by 80 inchesCalifornia king72 inches by 84 inchesWhy Choose a King Size Bed?Choosing a king size bed is not just about more sleeping space for you and your sleeping partner. Having plenty of room to sleep without knocking into your sleep partner is nice, but it may provide you with some health benefits.Improve Blood FlowStretching out your body instead of being confined to a small sleeping space can keep your blood flowing and prevent you from waking up with an uncomfortable pins-and-needles sensation.Sleep BetterThe ability to comfortably move without disturbing your sleep partner (or your sleep partner bothering you) may improve your sleep quality. This is also perfect if you or your sleep partner is a combination sleeper since they tend to toss and turn regularly.If you have a family, a king bed is also the best size if you have children who like to climb into bed with you at night.King Size VariationsKing size mattresses became standardized between the 1940s and 1950s, but mattress manufacturers have created other variations since then. These include the split king, California king, and Alaskan king. The size variations were a means to appeal to potential customers looking for more sleeping space and better comfort.Split KingA split king is the same size as a standard king, except the mattress is split down the middle. Split king mattresses are the same as two twin XL beds placed next to each other. If you and your sleep partner have different personal preferences regarding sleep, a split king could be the answer.You and your sleep partner can enjoy your own mattress, sleeping together snugly without having to compromise on comfort and support. If you want to enhance your comfort further, consider adding an adjustable base. An adjustable base allows you to elevate your body without disturbing your sleep partner. Raising the upper body may reduce snoring—both you and your sleep partner breathe better and enjoy a sounder sleep.California KingA California king measures 72 inches by 84 inches. It’s a bit narrower than a standard king, but a California king mattress is longer, perfect if you’re tall and need more legroom. California king size beds, or western kings, were first introduced in the 1960s in Los Angeles, California. This size was considered a step up in luxury from a king because a California king is longer.Alaskan KingAn Alaskan king bed is the biggest mattress size ever created at 108 inches by 108 inches. The Alaskan king is an excellent bed size if you have a large family and regularly co-sleep with your kids. You won’t see an Alaskan king in a mattress showroom because they take up a ton of space, but they are available to purchase online.Only a few mattress companies offer the Alaskan king—they may also have bedding, like comforters, bed sheets, and mattress protectors to match. However, you may have to hire a professional to create a custom box spring or bed frame since an Alaskan size is not available.FAQsIs a California king bigger than a king mattress?A misconception in the mattress industry is that a California king is the larger mattress compared to a king. However, Cal king beds have less surface area than a king. It’s not a huge difference, but you may feel differently based on your specific needs. For example, if you, your sleep partner, or both of you are six feet or taller, a California king size might be the best choice.What is the most popular mattress size?The most popular mattress size depends on your individual needs. Several popular sizes include twin, twin XL, queen, and king.TwinA twin mattress size is the best fit for small children. This size is the next step from a toddler bed. Twin mattresses are easy to transport and fit inside smaller rooms. You could even invest in bunk beds if you have at least two children. Bunk beds are a great way to accommodate more than one sleeper without taking up extra space.Twin XLTwin XL size mattresses are a better fit for single sleepers. The longer size makes it more comfortable for any height, one of the main reasons why twin XL beds are standard in college dorm rooms. Plus, if you have two twin XL mattresses, you can easily push them together to create a king size.QueenQueen size mattresses are most popular for couples and single adults. Queen beds cost less than a king or California king mattresses, but they still provide enough space to accommodate two people and fit inside small master bedrooms (at least 10 feet by 12 feet). Single adults will love the luxurious space from a queen-sized bed compared to a twin or full size mattress.KingKing mattresses, or eastern king beds, are the perfect size for couples. King beds provide lots of room so you and your sleep partner won’t feel crowded. This size can also fit small children if they tend to sneak into your bed at night.Do two twin beds make up a king mattress?No, because two twin size mattresses are only 38 inches by 75 inches each, while king size mattress dimensions are 76 inches by 80 inches. Instead, two twin XL mattresses make up a king or split king because twin XL beds have extra length. Split kings are the perfect bed if you and your sleep partner are looking for customized comfort and support.Which mattress size is better for couples—queen or king?Both are great options for couples, but choosing a queen or a king size depends on a few factors, mainly budget and room size. A queen mattress size is 60 inches by 80 inches and smaller compared to a king size at 76 inches by 80 inches. Queen mattresses may be smaller, but they’re less expensive and can fit most master bedrooms and guest rooms.King beds are larger, but more difficult to move. Even though king size mattresses are more expensive, they provide more space compared to a queen.What is the largest standard mattress size?The largest standard mattress size is the king bed. King mattresses are 76 inches by 80 inches and considered the most popular size for couples because of the personal luxury space it provides. Be aware that a king size isn’t for everybody.King mattresses cost the most because they contain more materials compared to other mattress sizes. Plus, they’re difficult to move and only fit inside master bedrooms at least 13 feet by 13 feet or larger—placing a king bed inside a smaller room may make you feel cramped in your bedroom.But, if you’re single and have the floor space and the money to enjoy a king size mattress, go for it.ConclusionKing size beds are an excellent choice for you and your sleep partner. They have lots of room to stretch out without you or your sleeping partner feeling cramped. King mattresses are the largest standard mattress size available. If you have a large master bedroom, at least 13 feet by 13 feet, and looking for a bigger size than a queen, a king size bed could be the solution.About the author Kiera PritchardKiera Pritchard’s curiosity around dreams and dreaming sparked her passion for sleep science. In addition to freelancing for eachnight, Kiera is also a physical trainer and strives to help others lead healthy lives while asleep and awake. Since joining our team, Kiera has compiled multiple sleep health guides offering our readers advice on how to improve their days and evenings. Find more articles by Kiera Comments Cancel replyLeave a CommentYour email address will not be published. Required fields are marked * Comment Name Email I agree to the Terms and Conditions of this website.