What Size Is Full Size Mattress? Exact Dimensions and How It Compares
If you’re asking “What Size Is Full Size Mattress”, you’re usually trying to figure out whether it will actually fit your room, your bed frame, and possibly two sleepers. This guide answers that directly and walks through the most common follow-up questions so you can decide if a full is the right size for you.
What Are the Exact Dimensions of a Full Size Mattress?
In the U.S. and most of North America, a standard full size mattress typically measures:
- 54 inches wide x 75 inches long
- In centimeters: about 137 cm x 191 cm
These measurements refer to the mattress itself, not the bed frame or headboard, which can add extra inches to the overall footprint.
A full size is sometimes called a “double bed”, but the dimensions are the same in modern usage.
Why Does the Size of a Full Mattress Matter?
Knowing what size is full size mattress helps you:
- Check if it fits your bedroom layout
- Decide if it’s right for one person or two
- Pick the correct sheets, mattress topper, and bed frame
- Compare it confidently to twin, queen, and king sizes
The full size falls in the middle of common mattress sizes: larger than a twin or twin XL, but smaller than a queen. This makes it a popular choice for solo adults, teens, and guest rooms where space is limited.
How Does a Full Size Mattress Compare to Other Mattress Sizes?
Here’s a simple comparison to put the full size in context:
| Mattress Size | Width x Length (inches) | Typical Use |
|---|---|---|
| Twin | 38" x 75" | Kids, small rooms |
| Twin XL | 38" x 80" | Taller teens, college dorms |
| Full (Double) | 54" x 75" | Solo adults, teens, guest rooms |
| Queen | 60" x 80" | Couples, main bedrooms |
| King | 76" x 80" | Couples wanting extra space |
A full mattress is:
- 16 inches wider than a twin, offering more shoulder and hip room for one person.
- 6 inches narrower and 5 inches shorter than a queen, which many couples find more comfortable for two.
Is a Full Size Mattress Good for Two People?
A common question after “What Size Is Full Size Mattress” is whether it works for couples.
- For two adults, a full can feel tight, especially if both sleepers move around a lot at night.
- For one adult plus a small child or pet, a full may feel adequate but cozy.
- For a single sleeper, a full usually offers plenty of space without taking over the room.
Many couples who prefer more personal space side-by-side lean toward a queen or larger, while a full is often viewed as a better everyday option for one person.
Will a Full Size Mattress Fit My Room?
To see if a full makes sense, consider both room size and furniture placement.
A full mattress (54" x 75") usually works well in:
- Smaller bedrooms where a queen might feel cramped
- Studio apartments where every square foot counts
- Guest rooms that double as offices or hobby spaces
When measuring, remember to:
- Add space for a bed frame, headboard, and footboard (these can add 2–6 inches or more in each direction).
- Leave walking space on at least one or two sides of the bed—many people prefer at least 24–30 inches of clearance where possible.
Are There Different Types of Full Size Mattresses?
In addition to the standard full, you may see some variations:
Full vs. Full XL
- Full: 54" x 75"
- Full XL (less common): about 54" x 80"
A Full XL keeps the same width but adds extra length, which can be helpful for taller sleepers who want more legroom without going as wide as a queen.
Full vs. Double
In current mattress sizing, “full” and “double” usually mean the same thing: 54" x 75". The term “double” is simply older, referring to “double the width of a single (twin) bed.”
What Bedding and Bed Frames Work with a Full Mattress?
When you know what size is full size mattress, you can match it with appropriately sized accessories:
- Bed frame / foundation: Labeled as “full” or “double” and designed to support 54" x 75"
- Sheets and mattress protectors: Look for full size on the package
- Comforters and duvets: Many people choose either full or full/queen; a full/queen size comforter may hang lower on the sides
If your mattress is thicker than average (for example, deeper pillow-top models), you may want deep-pocket full sheets so they stay securely in place.
✔️ Quick Mattress Takeaways
Key points to understand about “What Size Is Full Size Mattress”:
- Standard dimensions: A full size mattress is 54" wide x 75" long (about 137 cm x 191 cm).
- Also called “double”: In modern sizing, full = double, just different names.
- Best suited for:Single adults, teens, and guest rooms where space matters.
- For couples: Possible but often cozy or tight, especially for restless sleepers.
- Room fit: Works well in smaller bedrooms and multi-use spaces; remember to allow room for frames and walking space.
- Variations: A Full XL adds extra length (around 80") but keeps the same width.
- Bedding and frames: Always choose items labeled “full” (or “double”) to match 54" x 75".
Understanding exactly what size is full size mattress makes it easier to plan your bedroom, compare mattress options, and select bedding that fits properly, so your sleeping space feels intentional and comfortable.
