How mattresses measure up

Casper’s guide to finding the perfect size bed
Mattress Size Chart and Dimensions

Measurements & Dimensions


39” x 75”

Twin XL

39” x 80”


54” x 75”


60” x 80”


76” x 80”

CAL King

72” x 84”

Sizing up Your Situation

Beyond personal preference, there are various factors to take into account before picking a mattress size. For example: How big is your bedroom? Do you share the bed with a partner or pets? Is living space or sleeping space more important to you? We’ve illustrated all six standard mattress sizes to give you a better idea about which mattress is appropriate for you.

Twin mattress illustration


At 39 inches wide by 75 inches long, a twin mattress is the smallest bed on the market. Its compact footprint means it's ideal for children and single adults. A twin is also great for individuals with small living spaces, such as studio apartments.

Twin XL mattress illustration

Twin XL

The twin’s slightly longer cousin, the twin XL mattress is the most popular size for college dorm rooms. It’s five inches longer than a twin, making it 39 inches wide and 80 inches long. In addition to students, a twin XL mattress is a good solution for taller teenagers and individual adults with limited space.

The Long and the Short of It

The difference between a twin and a twin XL? The twin XL is five inches longer.

Full mattress illustration


A good starter mattress for young adults or recent grads living on their own for the first time, the full mattress is 54 inches wide and 75 inches long. Sometimes called a double, the full is 16 inches wider than a twin, but is not recommended for couples who like to share the bed with pets or their children. The full is also a smart choice for guest rooms.

Queen mattress illustration


The most popular mattress size around, the queen mattress fits best in a master bedroom that’s at least 10 x 10 square feet. At 60 inches wide and 80 inches long, the queen offers plenty of space for couples or individuals who like having extra room to move around in bed.

King mattress illustration


At 76 inches wide and 80 inches long, the king mattress is large enough to accommodate couples who share the bed with their children or a sizable pet (think: a great dane). Owning a king requires a spacious master bedroom, preferably at least 12 x 10 square feet.

Did You Know?

If you have an adjustable or split king bed, you can order two twin XL mattresses for your frame.

California King mattress illustration

California King

The longest mattress on the market, the California king mattress is a whopping 72 inches wide and 84 inches long. Its generous length makes it ideal for taller individuals, especially people more than six feet tall. Of course, people of average height might also benefit from a California king depending on how many people and pets are sharing the bed.

The Long and the Short of It

If you’re deciding between a king or California king, it all comes down to four inches. A king mattress is actually four inches wider than a California king, while a California king is four inches longer than a king.