Mattress Size Guide: Find the Right Bed Dimensions for Your Room

Imagine purchasing a new bed only to find out that it doesn’t fit in your bedroom or it's dwarfed by your room’s size. When it comes to selecting the perfect mattress, size matters more than you might think. Finding the right bed size is an essential part of getting quality sleep across your lifetime. 

This guide will help you choose the ideal mattress size and bed frame for your room dimensions, sleep preferences, and lifestyle needs.

Understanding Bed Sizes: Dimensions, Best Uses, and Room Fit

A key aspect of bed shopping is understanding the dimensions of different mattress sizes. Whether you need a compact option for a small room or a spacious mattress for ultimate comfort, choosing the correct mattress size is paramount. 

Here is a breakdown of standard mattress sizes, their dimensions, and the best scenarios for each:

What Size Bed and Mattress Do I Need?

Twin Mattress (38" x 75")

Dimensions:
A twin mattress measures approximately 38 inches wide by 75 inches long (96.5 cm x 190.5 cm), making it the smallest standard mattress size.

Summary:
The twin mattress is a popular choice for children’s rooms, smaller bedrooms, or guest rooms. It offers enough space for one child or an average-sized adult. Due to its compact size, it’s also easy to move around, making it perfect for smaller spaces or temporary sleeping arrangements.

Best For:
Ideal for children, teens, and adults who need a compact bed or for guest rooms with limited space.

Room Size:
A twin mattress fits best in rooms around 70 square feet. A room that’s at least 10’ x 10’ will comfortably fit a twin mattress and allow space for a dresser or nightstand.

Twin XL Mattress (38" x 80")

Dimensions:
A twin XL mattress measures approximately 38 inches wide by 80 inches long (96.5 cm x 203.5 cm), offering extra length compared to a standard twin bed.

Summary:
As the standard bed size for college dorm rooms, a twin XL mattress gives students room to stretch out but doesn’t offer any more width than a conventional twin-size mattress. Although this mattress is easy to move around, adults prefer a larger bed size once circumstances allow.

Best For:
Taller kids and students living in college dorms.

Room Size:
A twin XL mattress is ideal for narrow rooms or studio spaces, with a minimum recommended room size of 7’ x 10’.

Full Mattress (54" x 75")

Dimensions:
A full mattress measures 54 inches wide by 75 inches long (137 cm x 190.5 cm).

Summary:
The full mattress provides more space than a twin but still isn’t as large as a queen. It’s an excellent option for single adults who want extra room but don’t need the expansive space of a larger mattress. The full mattress is also suitable for two smaller individuals, though it may feel cramped for taller people.

Best For:
Individuals who need more space than a twin but don’t need the vastness of a queen, and those who share their bed with a child or a small adult.

Room Size:
A full mattress works best in rooms that are at least 10’ x 12’ or larger to ensure there’s enough room for the bed and additional furniture.

Full XL Mattress (54" x 80")

Dimensions:
A full XL mattress measures 54 inches wide by 80 inches long (137 cm x 203.5 cm), offering an additional 5 inches in length compared to the standard full mattress.

Summary:
The full XL mattress offers more legroom than the regular full mattress, making it a great option for taller individuals who need a little extra space. It is particularly beneficial for single sleepers who want more length but don’t need the width of a queen mattress.

Best For:
Taller individuals who find a standard full mattress too short.

Room Size:
A full XL mattress fits best in a room of at least 10’ x 16’ to allow ample space for other furniture and free movement.

Queen Mattress (60" x 80")

Dimensions:
A queen mattress measures 60 inches wide by 80 inches long (152.5 cm x 203.5 cm).

Summary:
The queen mattress is one of the most popular mattress sizes, offering ample space for two people without taking up too much room in the bedroom. It’s an excellent choice for couples who prefer a bit more space than a full mattress but don’t want to commit to a larger king size.

Best For:
Couples or individuals who want extra space for a more comfortable sleep, as well as guest rooms.

Room Size:
A queen mattress fits comfortably in rooms of at least 10’ x 10’, though a 10’ x 12’ room is recommended for a more spacious feel.

King Mattress (76" x 80")

Dimensions:
A king mattress measures 76 inches wide by 80 inches long (193 cm x 203.5 cm), providing an expansive area for two sleepers.

Summary:
The king mattress is the go-to choice for couples who want maximum space. With 16 additional inches of width compared to a queen, the king mattress offers plenty of space for both partners to move freely without disturbing each other during sleep.

Best For:
Couples who need extra personal space while sleeping, as well as larger adults.

Room Size:
A king mattress fits best in a room that is at least 13’ x 13’ for the most comfortable fit. For smaller rooms, a king mattress may feel cramped, but it can still work in rooms as small as 10’ x 12’.

California King Mattress (72" x 84")

Dimensions:
A California King mattress measures 72 inches wide by 84 inches long (183 cm x 213.5 cm), making it slightly narrower but longer than the standard king mattress.

Summary:
The California King is ideal for taller individuals who need additional legroom but don’t require the width of a king. It’s perfect for couples who want plenty of length but don’t need the extra width that comes with a king mattress.

Best For:
Taller couples or individuals who need more length for comfort.

Room Size:
A California King mattress is best suited for rooms that are at least 12’ x 14’ to allow for enough space to move around comfortably.

Considerations When Choosing Mattress Size

When shopping for a new bed and mattress, there are several critical factors to consider to ensure you make the best choice:

1. Health Needs: If you suffer from specific health conditions such as back pain, muscle discomfort, or acid reflux, you may need specialized beds. For instance, an  adjustable bed  can provide enhanced support and allow for custom sleeping positions to ease discomfort. Furthermore, you may need to opt for specific types of mattresses, such as memory foam or hybrid models, depending on the level of support required.

2. Bedroom Dimensions: It’s important to measure your room before purchasing a mattress to ensure the bed fits comfortably in the space. A bed that’s too large can make your room feel cramped, while a mattress that’s too small may leave you feeling confined. Properly sized mattresses will also allow for room for other furniture, like nightstands or dressers.

3. Sleeping Preferences: Each sleeper has different comfort requirements. Some people need firm support, while others prefer the contouring feel of memory foam. Understanding your comfort needs will help you make the right choice for mattress type, which in turn affects the best bed frame size.

Choosing the Right Mattress Type for Your Room

Along with the correct bed size, the mattress type plays an essential role in your overall sleep experience. Here’s a breakdown of the most common types:

• Innerspring Mattress: Featuring metal coils wrapped in fabric, innerspring mattresses are the most common type. They provide firm support and are ideal for people who sleep on their back or stomach. Innerspring mattresses come in various comfort levels, including firm, extra firm, and plush.

• Memory Foam Mattress: A memory foam mattress molds to your body’s shape, providing support and relieving pressure points. It’s perfect for individuals who experience joint or back pain, as it contours to the body and helps distribute weight evenly. Memory foam is especially beneficial for side sleepers and those looking for a more cradling feel.

• Hybrid Mattress: Combining innerspring coils and memory foam, hybrid mattresses offer the support of traditional innerspring with the comfort of foam. They are ideal for couples since they minimize motion transfer, ensuring you and your partner can sleep soundly without disturbing one another.

How to Properly Measure the Length, Width, and Depth of Your Mattress and Box Spring

Not sure which size mattress to choose? That’s when you need measurements to rely on, and it’s important to make sure they are accurate. If your mattress doesn’t fit your bed’s box spring, it can slide around when you move or create more wear and tear on the mattress, and you won’t get the best possible support. Here’s how to measure a mattress or box spring:

First, start by putting the mattress or the box spring on a flat surface. To determine the length, use a tape measure starting from the top edge (or the head) of the mattress or box spring down to the bottom edge. For width, measure from the left edge to the right edge. Finally, here’s how to measure mattress or box spring depth: Go from the bottom of the mattress or box spring that is resting on the ground up to the surface edge. (For mattresses, be sure to include any pillow-top in your measurements.)

If you’re going to be mattress shopping, measure your box spring beforehand and then bring the dimensions in when you visit Sit ‘n Sleep. That’s how to tell what bed size you have, and our sleep consultants can make sure you select a mattress that will fit properly for the best sleep experience.

Find the Right Bed and Mattress at Sit 'n Sleep

At Sit ‘n Sleep, our knowledgeable sleep consultants are here to help you find the perfect mattress size and bed frame for your needs. Whether you’re looking for a twin, queen, or California king, we have a wide selection of top-quality mattresses from trusted brands like Sealy, Tempur-Pedic, Beautyrest, and more. Stop by one of our Southern California locations, chat with us online, or call us at (800) 908-0354 to schedule a consultation.

Frequently Asked Questions (FAQs)

Need more information? Start here, and then get in touch with us to get the mattress that meets your exact needs.

Can Full Size Sheets Fit on a Queen Bed?

Full size sheets won’t fit a queen bed. Full mattresses are 54 inches by 75 inches, while queen mattresses measure 60 inches by 80 inches. Full sheets will be too short in both width and length, so they won’t provide full coverage. Always match your sheets to your mattress, which is why it’s important to know how to measure a mattress size.

Can a King Size Bed Fit in a 10X10 Room?

A king bed typically isn’t recommended for rooms that are 10X10 or smaller. A standard king is 76 inches by 80 inches (or more than 6 feet by 6 feet). That will leave little room for walking space, or for other bedroom furniture. 

What Size Room Is Best for a King Size Bed?

Given that a king bed is over 6 feet in length and width, the room should be a minimum 12X12. This gives you plenty of space to walk comfortably around the bed and have other furnishings like nightstands or dressers without the room feeling cramped. Know how to measure bed size to ensure your bed will fit the space.

Can a Full Size Bed Fit in a 10X10 Room?

Yes, a full size bed fits comfortably in a 10X10 room because it is 54 inches by 75 inches. This still leaves space for other furniture and walking paths around the bed. That makes a full size bed a popular choice for smaller rooms, like a child’s bedroom or a guest room.

Can a Queen Size Bed Fit in a 10X10 Room?

A queen bed could fit in a 10X10 room, but it will be a tight squeeze. Queen mattresses measure 60 inches by 80 inches, so there won’t be much space once the bed is in place. If you opt for a queen bed, keep the bed frame streamlined and keep other furniture to a minimum.

Can I Fit Two Full Size Beds in One Room?

Two full size beds can fit in one room, depending on whether the dimensions are large enough. Two beds would probably be too big for a 10X10 room, but will fit better in a space that is 12X12 or larger. 

What Size Bed Can Fit in a 10X10 Room?

The best beds for this room size are twin, twin XL, or full. Before buying any bed, plan where the bed and any other furniture will be placed, allowing room for doors to open and for clear walking paths.

Visit a Sit 'n Sleep store to speak with one of our experts and find the right size mattress for your bedroom!