A new bed is an investment. Whether you’re buying a bed for the first time or replacing an old mattress, knowing the best size for your situation helps you narrow down potential options and prevents you from buying a mattress that’s too big for your living space.In our article, we break down the different mattress sizes and discuss other factors to help you choose the right mattress. Choosing the right size bed ensures extra room for lamps and nightstands, leaves plenty of walking room, and helps you avoid sleeping in a cramped bedroom.Mattress Size and DimensionsMattress SizeDimensions (IN)Dimensions (CM)Crib27 inches by 52 inches68.5 cm by 132 cmTwin38 inches by 75 inches96.5 cm by 190.5 cmTwin XL38 inches by 80 inches96.5 cm by 203.2 cmFull54 inches by 75 inches137.1 cm by 190.5 cmFull XL54 inches by 80 inches137.1 cm by 203.2 cmQueen60 inches by 80 inches152.4 cm by 203.2 cmShort Queen60 inches by 75 inches152.4 cm by 190.5 cmOlympic Queen66 inches by 80 inches167.6 cm by 203.2 cmKing76 inches by 80 inches193 cm by 203.2 cmCalifornia King72 inches by 84 inches182.8 cm by 213.3 cmAlaskan King108 inches by 108 inches274.3 cm by 274.3 cmTexas King80 inches by 98 inches203.2 cm by 248.9 cmWyoming King84 inches by 84 inches182.8 cm by 182.8 cmCrib Size Mattress DimensionsMeasurement: 27 inches by 52 inchesCrib mattresses are built to fit inside crib frames and meant for babies and toddlers. Crib mattresses are the perfect size for babies up to 18 months old, or when the baby grows to three feet tall. When babies are almost two years old, it may be time to “graduate” to a twin bed.Twin Size Mattress DimensionsMeasurement: 38 inches by 75 inchesTwin mattresses are one of the most versatile beds available. Twin size beds are best for children. The small, compact size can hold a child’s growing body and provide room to stretch out. Twin size mattresses are also easy to maneuver and fit inside small living spaces.If you have more than one child sharing a room, investing in a bunk bed might be a great solution. Bunk beds stack two to three mattresses, but only take up a small amount of space. Your children can enjoy more playroom and still have a nice sleeping area.Twin XL Size Mattress DimensionsMeasurement: 38 inches by 80 inchesTwin XL mattresses are about the same size as a regular twin, except they’re 5 inches longer. The extra length gives your child more legroom. Twin XL beds are an excellent mattresses for teenagers and young adults, which is why this size is common in college dorm rooms.College students can comfortably stretch their legs, no matter how tall they are. Like the standard twin, twin XL size mattresses are easy to move and fit nicely inside a bunk bed frame.Full Size Mattress DimensionsMeasurement: 54 inches by 75 inchesSingle sleepers, like teenagers and single adults with limited living space, will love full size beds. Full mattresses, or double beds, as they’re also called, are the same length as a twin bed, but come with 16 extra inches in width.A full size mattress is an excellent solution if you’re looking for a wider bed, especially if you tend to toss and turn at night. The extra width gives you more sleeping space without fear of rolling off the mattress.Full XL Size Mattress DimensionsMeasurement: 54 inches by 80 inchesA full XL mattress is similar to a full bed, except it is 5 inches longer. Those extra inches are great for single adults who are taller than 6 feet. Taller adults can comfortably stretch their legs out in a full XL size bed.Queen Size Mattress DimensionsMeasurement: 60 inches by 80 inchesQueen mattresses are one of the most popular bed sizes on the market. If you’re single, you’ll love the luxurious space the queen bed provides. You can easily spread out on the bed without worrying about falling out.For couples, the queen size bed is the perfect budget size. Queen size mattresses offer each person 30 inches of personal space but fit comfortably inside most standard bedrooms, about 11 feet by 12 feet. They’re also less expensive than larger mattress sizes, like a king and California king.Short Queen Size Mattress DimensionsMeasurement: 60 inches by 75 inchesUnlike the standard queen size, the short queen mattress is 5 inches shorter—75 inches long instead of 80 inches. This may seem like a drawback, but a short queen is actually perfect for RVs and trailer homes. The shorter length allows for more bedroom space.RVs and trailer homes tend to utilize as much space as possible to mimic the feel of a regular home within a limited space. A short queen bed still gives you plenty of sleeping room compared to smaller sized mattresses.Olympic Queen Size Mattress DimensionsMeasurement: 66 inches by 80 inchesThe Olympic Queen is 6 inches extra longer than a regular queen size, so you and your sleep partner can enjoy more personal space. If either of you is a combination sleeper, having that extra room to move around can be a great benefit. There’s less risk of disturbing your partner by bumping into them. Plus, you both have more room to stretch out without feeling cramped.King Size Mattress DimensionsMeasurement: 76 inches by 80 inchesKing size beds are the largest standard mattress size available. They’re especially popular for couples. King mattresses give you and your sleep partner 38 inches of personal space. That’s the equivalent of a twin XL size mattress for each of you.The king bed gives plenty of room to stretch out without bumping into your partner. But, because king size mattresses are so big, they can be challenging to maneuver and fit best in master bedrooms at least 13 feet by 13 feet. Another variant of the standard king is the split king.Split King Size Mattress DimensionsThe split king size is the same as a regular king, except it’s two separate twin XL mattresses placed side by side. Split kings are the best mattresses for couples who want their own customized levels of comfort and support. You and your partner can choose a twin XL bed, based on your personal preferences. For instance, you may prefer a medium feel, while your partner likes a firmer surface.California King Size Mattress DimensionsMeasurement: 72 inches by 84 inchesCalifornia king mattresses have a slightly smaller surface area than standard king beds, but they provide plenty of sleeping space for you and your partner. A California king bed is longer and narrower than a king—perfect for taller couples. Cal kings provide more legroom so that you can comfortably stretch out and sleep better without feeling cramped.Alaskan King Size Mattress DimensionsMeasurement: 108 inches by 108 inchesAlaskan king size mattresses are one of the biggest bed sizes the mattress industry offers. The bed measures 108 inches by 108 inches—that’s 9 feet by 9 feet! This size is perfect for large families.Texas King Size Mattress DimensionsMeasurement: 80 inches by 98 inchesTexas king beds are the second-largest mattress size and are excellent for tall sleepers who prefer lots of sleeping space. Texas kings are smaller than Alaskan kings and narrower than Wyoming kings. A Texas king mattress is easier to fit inside a large master bedroom than an Alaskan king. Plus, they won’t be as expensive because Texas kings are smaller.Wyoming King Size Mattress DimensionsMeasurement: 84 inches by 84 inchesA Wyoming king is the smallest oversized king mattress variation. Wyoming king-sized beds are still impressively large, about 7 feet by 7 feet, but they won’t cost as much or take up as much room as an Alaskan or Texas king. Children can co-sleep with their parents in a Wyoming king, but the mattress may not be able to fit as many people as other oversized beds.How to Choose the Right Mattress SizeDon’t rush and choose any size mattress, or you could end up with buyer’s remorse. The ideal bed size depends on room size, who’s using the mattress, and budget. Using this information can help you find the best mattress and create a comfortable atmosphere.Room SizeKeep in mind that when you decide on the right mattress size, take into account the size of your bedroom. You don’t want to end up with a mattress that takes up most of the living space. What about adding other furniture, like a desk or a nightstand? Plus, an overcrowded bedroom can cause you stress and lead to trouble sleeping.Choosing a mattress to accommodate your bedroom, while leaving space for additional furniture and walking space gives you more room for storage.Who’s Using the MattressWho’s using the mattress is the most important factor to consider when choosing a new bed. You don’t need to spend extra money on a king or California king size mattresses for a single adult. The larger size may feel too big for one person.For couples, larger mattress sizes are better. Queen, king, or California king beds give you and your partner personal space to sleep better at night. Smaller mattress sizes don’t offer enough sleeping space for two people, and you may find your sleep interrupted by each other’s movements.BudgetAnother major factor when choosing a bed size is cost. The larger the mattress, the higher the price tag. Bigger beds simply contain more materials, making them more expensive.The two most popular budget mattress sizes are twin XL and queen. Twin XL beds are inexpensive and perfect for single adults. They have enough space for one person and fit in most bedrooms. Twin XL mattresses are also ideal for studio apartments, where space is limited.Queen beds are excellent options for couples on a tight budget. This size has plenty of room for two individuals but doesn’t take up too much living space. Queen size mattresses are also an excellent choice for guest rooms. Single sleepers can enjoy the comfortable sleeping area, while couples can rest easy without feeling overcrowded.FAQsWhat are the dimensions of a single bed?A single bed is smaller than a twin, but larger than a crib, measuring 30 inches by 75 inches. Single beds are also known as toddler mattresses. When a child outgrows their crib, a single, or toddler bed is the next step, especially if you’re worried a twin size will be too big.What size are double beds?Double beds are the same size as full mattresses, measuring 54 inches by 75 inches. In the past, double beds were considered the ideal choice for couples until queen size mattresses rose in popularity in the 1950s. Today, full size mattresses are better suited for single adults instead of couples. Two people may feel overcrowded in a double bed.What is the best thickness for a mattress?For a long-lasting mattress, choose a bed at least 10 to 12 inches thick. This mattress thickness can better handle constant wear and tear from most body types without prematurely sagging. They also have thicker comfort and support layers so that you can fully enjoy your mattress for years.Thinner mattresses can’t offer as much support. Regular use combined with sleep movements can break down materials faster. You could end up having to replace the bed sooner than you expected.Is it better to get a high or low profile bed?Choosing between a high or low profile comes down to personal preference. Both profiles have benefits and drawbacks. Low profile beds make it easier to climb in and out of bed, while high profile beds can give more storage space underneath the bed frame.Is putting your bed on the floor bad?Some mattress companies advertise that their mattress models don’t need additional support from a mattress foundation or a bed frame. A memory foam mattress is a classic example. Memory foam is dense and needs support from a flat, even surface than a wide, metal frame. However, placing your mattress directly on the floor exposes you and your bed to more dust mites, allergens, and bacteria.It’s better to keep your bed off the floor so it isn’t as exposed to allergens. If you’re looking for a solid surface, consider a platform bed. Platform bed frames better support dense materials like memory foam and latex.ConclusionChoosing the right mattress size is just as important as deciding on firmness level and mattress type. A bed that fits comfortably inside your bedroom or guest room gives a comforting appeal to you and your guests. If you choose just any mattress size, you could end up with a cramped room without any additional space for furniture, storage, or moving around.