Mattress Sizes and Dimensions

Thinking about upgrading your old mattress? Choosing the right size is the first step in finding the perfect new mattress, and helping you to avoid the costly and frustrating hassle of having to return a mattress that doesn’t fit your bedroom (or your needs). And if you’re making the leap to an entirely new mattress size, choosing the right dimensions is doubly important, as you have to consider how much sleeping space that you’ll need for ultimate comfort and the best night’s sleep possible.

Mattress Size Chart

The good news is that you can use the convenient mattress sizing charts below to guide you in making the right size selection, and the best choice for your new mattress.


38” x 75” x 10”

Twin XL

38” x 80” x 10”


54” x 75” x 10”


60” x 80” x 10”


76” x 80” x 10”

Cal King

72” x 84” x 10”

Twin Mattress Dimensions

While adults can sleep on a twin size mattress, it is most commonly used with children’s bed frames, as it is the smallest sleep area of all the standard mattress sizes. Twin mattress dimensions are typically 38 inches wide by 75 inches long (38” W x 75” L).

Check out Lull's Twin Mattress

Twin XL Mattress Dimensions

With 5 inches of additional length, the twin XL (extra long) mattress is a great option for college students due to its extra leg space – this size mattress is regularly found in university dorm rooms. Twin XL mattress dimensions are typically 38 inches wide by 80 inches long (38” W x 80” L).

Check out Lull's Twin XL Mattress

Full Mattress Dimensions

Also known as a “double mattress,” a Full size mattress is a great choice for growing children, but usually doesn’t provide enough space for two adults to share comfortably, especially if they are over 5’8” tall. Full mattress dimensions are 54 inches wide by 75 inches long (54” W x 75” L).

Check out Lull's Full Mattress

Queen Mattress Dimensions

The most popular mattress size choice for the average adult sleeper, the Queen size mattress provides more sleeping space than the Full mattress, and is usually offers enough space for two adults to sleep together in comfort, especially if you and your partner enjoy cuddling up with one another at bedtime. Queen size mattress dimensions are 60 inches wide by 80 inches long (60” W x 80” L).

Check out Lull's Queen Mattress

King Mattress Dimensions

The best choice for partners that enjoy their own space when sleeping, or for those that share their bed with kids or pets, the King size mattress provides ample room for a quality night’s sleep. Essentially two Twin XL mattresses merged together, the King size mattress dimensions are 76 inches wide by 80 long (76” W x 80” L).

Check out Lull's King Mattress

Cal King Mattress Dimensions

For people that are over 6’ tall or enjoy “family sleeping” with kids or pets, the California King size mattress is a great choice. A “Cal” King mattress is 4 inches narrower and 4 inches longer than a traditional King size mattress, giving tall sleepers plenty of room to stretch their legs. California King size mattress dimensions measure 72 inches wide by 84 inches long (72” W x 84” L).

Check out Lull's Cal King Mattress

Have Mattress Dimensions Changed?

The short answer is yes. You may find references to Twin mattress sizes as 39” W x 74” L. And Twin XL mattress sizes as 39” W x 80” L. Many manufacturers round-up dimensions of their mattresses to make them appear larger. In some cases by over 1 inch. The dimensions displayed on this page are more accurate measurements of your new mattress.

Are Bed Frame Sizes Standardized?

Unfortunately, the answer to this question is no. Bed frame manufacturers leave one to two inches around the mattress to fit into their frames. The amount of clearance will vary by manufacture. Take time to measure your sleeping space. This will ensure your bed frame will fit and leave room for movement around the bed.

Watch How a Bed Can Fit Into a Small Box
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