A Complete Guide to Mattress Dimensions
To help you select the appropriate mattress size, we’ve put together a guide to standard dimensions and which mattress can best suit your needs.
Mattress Size |
Dimensions in IN | Dimensions in CM | Comfortable Fits |
---|---|---|---|
King |
76" x 80" | 193 X 203.2 cm | Two sleepers, with room to spare |
California King |
72" x 84" | 182.9 X 213.4 cm | Two taller individuals |
Queen |
60" x 80" | 152.4 X 203.2 cm | Single sleepers, couples, or even pets |
Full |
54" x 75" | 137.2 X 190.5 cm | Single sleepers or couples (if you don't mind being close) |
Twin XL |
38" x 80" | 96.5 X 203.2 cm | Tall single sleepers |
Twin |
38" x 75" | 96.5 X 190.5 cm | Single sleepers |
Find your perfect mattress
Standard Mattress Sizes
While mattress sizes vary from brand to brand, you can expect to find the following measurements for each type.
What are the dimensions of a King Mattress?
The dimensions of a king mattress are 76 in x 80 in. A king-size mattress is the best choice for parents who want to co-sleep with their children. These are the broadest available standard size. Accessories are also widely available. While spacious and luxurious, king mattresses occupy ample space, making smaller rooms look cramped.
Minimum room size: 12 ft x 12 ft
Best for: Couples who share a bed with pets or children

What are the dimensions of a California King Mattress?
The dimensions of a California king mattress are 72 in x 84 in. These are the longest available standard size but are slightly narrower than a regular king. Plus, with this extra length comes a hefty price tag. Accessories for California king beds are also not as readily available.
Minimum room size: 12 ft x 12 ft
Best for: Taller couples with one or more children

What are the dimensions of a Queen Mattress?
The dimensions of a queen mattress are 60 in x 80 in. This is the most popular size on the market, making them highly available wherever you shop. It fits into almost any room, without making your space look cramped. You’ll typically find them in master bedrooms for couples who don’t share a bed with pets or children.
Minimum room size: 10 ft x 10 ft
Best for: Couples who need more space than a full mattress

What are the dimensions of a Full Mattress?
The dimensions of a full mattress are 54 in x 75 in. Sometimes called a double, a full mattress is a spacious choice for young adults who tend to toss and turn in their sleep. It’s affordable and versatile, making it a popular choice among couples or for use in guest rooms.
Minimum room size: 10 ft x 11 ft
Best for: Young adults with more room space or couples

What are the dimensions of a Twin XL Mattress?
The dimensions of a twin XL mattress are 38 in x 80 in. These are five inches longer than the standard twin size, making them ideal for taller sleepers. If you have limited space in your room, a twin XL mattress can provide optimal length without compromising additional square footage. You can also use twin XL mattresses together if you have a split-king frame with an adjustable base.
Minimum room size: 8 ft x 10 ft
Best for: College dorms or single sleepers

What are the dimensions of a Twin Mattress?
The dimensions of a twin mattress are 38 in x 75 in. Twin mattresses are the smallest of all standard sizes and are best for adolescents or petite single sleepers. They also make ideal daybeds and are suitable for bunk beds. Accessories and bed frames for twin-size mattresses are highly available and affordable as well.
Minimum room size: 7 ft x 9 ft
Best for: Children or for use with bunk beds

Other Mattress Sizes
The dimensions of a split king mattress are 76 x 80 in. Split king mattresses are the same size as a king mattress except it is two twin xl mattresses side by side. This allows couples to adjust their sleeping preferences with out impacting the other.
Minimum room size: 12 ft x 12 ft
Best for: Couples that have different sleeping preferences
The dimensions of a crib are 27.25 x 51 in. Crib-size mattresses should not be more than six inches thick to provide optimal support. The United States federal government standardizes crib sizes to ensure the safety of infants. As such, finding accessories like bed sheets is very easy, and they are available in standardized sizes anywhere.
Minimum room size: Any standard room size
Best for: Newborns and young toddlers
The dimensions of a small single mattress are 30 x 75 inches. Because small single and twin mattresses have the same length, people sometimes use the terms interchangeably. However, small single mattresses are narrower and more ideal for smaller spaces, such as dormitories or shared rooms.
Minimum room size: 7 x 10 ft
Best for: Adolescents or spare mattresses
The dimensions of an Olympic queen mattress are 66 in x 80 in. Olympic queen mattresses are six inches wider than a standard queen and are commonly found in mobile homes and campers. However, finding accessories for Olympic queen beds is often quite difficult. Most couples compensate through custom sheets or extra-large blankets.
Minimum room size: 10 ft x 10 ft
Best for: Couples who want extra sleeping space but can’t accommodate a king
The dimensions of a full XL mattress are 54 in x 80 in. Compared to a standard full, a full XL mattress is five inches longer than a traditional full. This is much more suitable for taller sleepers who don’t need extra width. A full XL can also accommodate couples with limited space.
Minimum room size: 10 ft x 11 ft
Best for: Taller sleepers who want more space
How to choose the right mattress size
When picking the right mattress, there is more to consider beyond its dimensions and minimum room size. Mattresses directly impact the quality of your sleep and should be considered an investment. Keep these factors in mind when shopping for a new mattress:
Sleeping Partner
One of the most critical factors when picking a mattress size is who you are sharing the bed with. While a full mattress suits most couples, it may not suit couples with children or pets. A king mattress might be best if you share a bed with multiple people.
Height
Most beds are wide enough for at least one person but may not always be long enough. For example, a twin bed might be wide and long enough for an average-height sleeper but certainly won’t be able to accommodate someone over 6’5”.
Room Size
Your bed should leave enough space for the rest of your furniture. As a rule of thumb, you’ll want to leave at least two feet of free space on each side of your bed to ensure you can move around comfortably.Also, consider door and staircase width, as these factors can dictate how you maneuver your mattress.
Budget
You should always consider your budget when shopping for a new mattress, but don’t make it your priority. Mattresses are an investment. Purchasing a high-quality mattress can save you more in the long run, as it can help you avoid premature deterioration.
Get overall comfort with the right mattress
Choosing a mattress can be confusing, especially when facing many options. However, you can make the process easier by considering the size of your room, height, budget, and whether you plan to share a bed with someone else.
We’re here to help you find that just-right fit — take our Mattress Quiz for personalized recommendations based on your sleep habits.
Frequently Asked Questions
Measure a mattress from head to foot to get the length and side to side to get the width. Depending on your bed base, you may also need to measure a mattress’ depth before purchasing.
Yes, full mattresses are big enough for two people and are popular among couples. However, couples with specific sleeping preferences might benefit more from a queen or king mattress. Alternatively, you can get two twin XLs to create a split-king and use an adjustable frame.
Read our article to understand pros and cons: Full mattress vs Queen Mattress.
The current most popular mattress size is the queen, which can suit single sleepers and partners. Shopping for accessories like sheets and duvets is easy as well, as they are highly available.
Technically, you can use two twin XL mattresses on a split-king bed frame. This can benefit couples with different sleeping preferences and needs.
Also, consider king vs California king differences.
While a standard pillow size is often good enough for any sleeper, some pillows specifically suit queen and king mattresses. If you tend to toss and turn in your sleep, buying a larger pillow can also help enhance your sleep.
Try Purple in 3,043+ Stores
Experience our industry-leading GelFlex® Grid in Mattress Firm, Ashley, Raymour & Flanigan, Mathis, Rooms To Go and other top retailers around the country.
