Mattress Guides

What’s the Difference Between a Double Bed and Full Size Mattress? 

The terms “double bed” and “full size mattress” are often used interchangeably, which can be confusing when shopping for a new mattress. However, both names refer to the same mattress size: 54 inches wide by 75 inches long.

This mattress size is popular among single adults, teenagers, and guest rooms because it offers more space than a twin bed while still fitting comfortably in smaller rooms. This article explains its history, dimensions, benefits, variations, and how it compares to other mattress sizes.

Key Takeaways

• A double bed and full size mattress are the same size: 54″ × 75″.
• “Double bed” is the older term, while “full size mattress” is the modern industry standard.
• Ideal for single sleepers, teens, and guest rooms.
• Offers a good balance between comfort and space efficiency.
• Not ideal for long-term sleeping for two adults.
• Couples usually sleep better on a king or queen-size mattress.

Quick Answer: Are Double Bed and Full Size Mattress the Same?

Yes. A double bed and a full size mattress are exactly the same in terms of dimensions: 54 inches wide and 75 inches long.

The only difference is the name:

• “Double bed” = traditional term
• “Full size mattress” = modern, industry-preferred term

Why Two Different Names Exist

The confusion comes from how mattress sizing has evolved over time.

Originally, the term “double bed” was used because the mattress was designed for two people to share. At the time, it was one of the largest available mattress sizes.

As sleeping preferences changed and larger beds like queen and king sizes were introduced, manufacturers began using the term “full size” to better describe it as a complete sleeping surface for one person rather than a shared bed.

Today, both names are still used, but they refer to the same mattress.

History of the Double Bed

As its name suggests, double beds were initially designed for two sleepers. However, before the 1940s, doubles were one of the few mattress sizes available. These beds were also one of the largest, which is perhaps where the name “full” comes from.

In the 40s, couples could choose to sleep on two separate twin beds or share a double bed. After the economic boom of the 1950s, Americans began to demand bigger, more luxurious home furnishings. The average American height and weight also began to increase at this time, creating an urgent need for a more spacious mattress.

As the demand for queen and king size mattresses grew, double beds were no longer a popular choice for couples. With only 27 inches of space per side, a full mattress is often too confining for two adult sleepers. A queen or king size bed offers couples more personal space to stretch out.

Dimensions of a Double/Full Mattress

Double beds measure 54 inches wide by 75 inches long. While these mattresses have the same length as a twin size bed (75 inches), they are 16 inches wider. For children and teenagers who have outgrown their twin mattress, a double bed is a good choice. Growing kids need plenty of room to move around and get comfortable during the night.

Single sleepers who prefer a bigger bed, but have a smaller room, may also like a double bed. These mattresses fit comfortably in most standard-sized bedrooms, including those that measure 10 feet by 10 feet (100 square feet).

Size Variations

Full XL or Double XL

As you shop for a full/double mattress, you may come across two size variations. Mattresses labeled “full XL” or “double XL” have the same width as standard full/double beds. However, the XL version of this mattress size measures 5 inches longer. The extra length is great for taller individuals in need of more legroom. With a total of 80 inches in length, tall sleepers won’t wake up with their feet dangling off the end of the bed.

Full/double XLs are not very common, but they are available at some online mattress retailers. When purchasing an XL model, keep in mind that accessories, such as sheets and bed frames, may be harder to find. Since this is not a popular size, not all manufacturers offer bedding that accommodates the extra length. As you shop, look at the dimensions of bedding and bed frames this will help you determine if the item will fit a full/double XL mattress.

Small Double

Although they are not very common in the US, mattresses labeled “small doubles” measure 48 inches wide by 75 inches long. This size is typically found in the United Kingdom and Ireland. Small doubles may also be referred to as a “three-quarter bed.” Like a standard double, small doubles are not recommended for two sleepers.

How Do Full/Double Beds Compare to Other Mattress Sizes?

In addition to double beds, there are several other standard size mattresses available in the United States. The most common include twin, twin XL, queen, king, and California king. Below, we explain how full/double size mattresses compare to these other sizes.

As we mentioned above, twin and full size mattresses both measure 75 inches long, but fulls are 16 inches wider than twins. Both sizes are suitable for most bedroom sizes, while still leaving enough space for furniture.

Twin XL mattresses measure 38 inches wide by 80 inches long. They have less width than a full but are 5 inches longer. Twin XL beds are typically used in college dorm rooms to accommodate taller students. Some bunk beds are also now available for twin XL mattresses. Although the length may work for most sleepers, some adults find the width of a twin XL too confining.

Queen mattresses are 6 inches wider and 5 inches longer than a full size. With 30 inches of space per side, a queen bed works well for most couples. This size is also a popular option for a guest room or a vacation home. However, if your family prefers to co-sleep, you may need more width so you, your partner, and your children can sleep comfortably. In most cases, a king size mattress works best. The extra width of a king bed offers 38 inches on each side of the bed.

California king beds are 4 inches narrower than a king, but 4 inches longer. Taller couples may prefer a bed with additional legroom.

If you decided to purchase a king or a California king mattress, be sure you have adequate space first. Larger mattresses require a room that measures at least 10 feet by 12 feet (120 square feet). A master bedroom that measures 14 feet by 16 feet (224 square feet) works even better in most cases. This room size should leave at least 2 to 3 feet of space around the mattress to make getting in and out of bed more comfortable.

Read Also: King vs. California King Size Mattress

Standard Mattress Sizes

Read Also: Twin vs Full vs Queen: Which Mattress Size Is Right for Your Space?

Why Choose a Full Size Mattress?

A full size mattress offers several practical benefits:

• Limited Space: When shopping for a new mattress, consider the size of your space. For a small studio apartment or a house with small rooms, a queen or king mattress may not be a good fit. However, a full size bed fits well in most spaces, without causing the room to feel overcrowded. A double bed offers solo sleepers more room to get comfortable, without sacrificing too much living space.
• Versatile: Full size mattresses are suitable for children, growing teenagers, and single adults. They fit well into most rooms and are readily available online. It is also easy to find accessories, such as foundations, sheets, and comforters for a double bed.
• Budget-Friendly: Full size beds are a budget-friendly option when shopping for a child’s room or guest room. Full size bedding and mattress foundations are also less expensive than their queen and king size counterparts.
• Easy to Move: Queen and king size mattresses can be heavy and difficult to move. If you plan to relocate soon, a full size bed may be the best choice. Double beds are typically lightweight and will easily fit into a van or small moving truck.

Read Also: Two Adults on Full Size Mattress

Is a Double Bed Big Enough for Two People?

This is one of the most important questions buyers ask. Technically, yes a double bed can fit two people. Practically, it’s often not comfortable for long-term use.

Each person gets about 27 inches of space (less than a crib’s width per adult).

That means:

• Limited movement space
• Higher chance of disturbing your partner
• Less comfort for taller or larger individuals

For short stays or occasional use, it can work. But for daily sleeping, most couples prefer a queen or king size mattress.

Who Should Choose a Full Size (Double) Mattress?

A full size mattress is actually a great choice for many sleepers, especially if used correctly.

1. Single Adults

If you sleep alone, a full size mattress gives you:

• Enough space to stretch comfortably
• A more luxurious feel than a twin bed
• Better sleep quality without taking too much room space

2. Teenagers

Teenagers often outgrow twin beds quickly. A full size mattress:

• Supports growing bodies
• Provides extra sleeping space for comfort
• Lasts through college years

3. Guest Rooms

If you’re furnishing a guest room, a full size bed is ideal because:

• It fits in smaller rooms
• Comfortably accommodates one adult
• Can sometimes fit two guests for short stays

4. Small Apartments or Studios

If space is limited, a full size mattress offers a good balance between comfort and room efficiency.

Double Bed vs Queen Bed: A Common Confusion

Many buyers upgrade from a full size mattress to a queen because of comfort differences.

Even a 6-inch difference in width makes a noticeable impact in sleep comfort.

Read Also: Queen vs Full Mattress: Which Size Is Right for You?

FAQs

How wide is a full size bed frame?

Most modern bed frames measure 1 to 2 inches wider and longer than the mattress itself. This extra space accounts for bedding that may hang down the sides and end of the bed. Therefore, a full size bed frame should measure 55 to 56 inches wide and between 76 to 78 inches long.

Are full size mattresses big enough for two people?

Full size mattresses are 54 inches wide, which leaves 27 inches on each side of the bed. While two people may fit on a full size bed, they will not sleep comfortably. Although larger beds require more space, couples typically sleep better on a queen or king size bed.

What’s the difference between a full XL and a queen bed?

A full XL mattress measures 54 inches wide by 80 inches long, while a queen size bed measures 60 inches wide by 80 inches long. These two sizes have the same length, but a queen is 6 inches wider than a full XL.

Can queen sheets fit a full bed?

No. Queen size sheets will not fit a full size bed. Queens beds are longer and wider than a full mattress. Sheets designed for a queen will not fit snug on a full-size bed, leaving extra fabric on the side. This material may bunch up as you move throughout the night, causing discomfort and sleep disruptions.

Should I buy a queen or full bed?

If you are a solo sleeper looking for a more luxurious sleep space, a full bed is a good option. However, if you are over 6 feet tall, a full XL or a queen size bed may be more comfortable for you.

Most couples prefer a queen or king size bed. Full size mattresses are too confining, even for smaller couples. The right bed size will ultimately depend on your body type and whether you plan to co-sleep with children. Queen size mattresses typically work well for most couples, but those who prefer to co-sleep should select a king size bed.

Conclusion

Although the United States has standard mattress sizes, the various names can make selecting the right size confusing. To ensure you are bringing home the best mattress, look at the bed’s dimensions and compare those to your bedroom. This is also a great way to shop for bedding, mattress foundations, and bed frames.