What You Need To Know About Mattress Sizes in the U.S.

If you are looking to buy a new mattress, you're probably overwhelmed with number of factors you need to consider. Mattress size is one of those factors that is incredibly important factor to get right. This brief article explains everything you need to know, so let's get on with it.


Why Is Mattress Size So Important?

  1. Knowing your mattress size is essential for matching the size of the bed to the person using it. Remember, a mattress should last between 8-10 years. You don't want to spend those years with your feet overhanging the edge of the bed! How uncomfortable would that be! Make sure this mattress fits you so that you can enjoy a good night's sleep.
  2. It's important for planning your bedroom layout. How do you everything will fit if you don't know the size of everything you want to put in your bedroom? Get your measurement right the first time - especially for the mattress and bed frame as they are probably the largest items in your bedroom.
  3. You also need to know your mattress size in order to select the correct sheets and bedding for a proper fit.

How To Measure For The Correct Mattress Size?

Mattress size is determined by the dimensions of the top of the mattress. 

Standard Twin Mattress. Image Source.

To find the size of an existing mattress, measure the width and length of the top to the nearest inch.

Compare the results against the common U.S. mattress sizes for older children and adults, as shown below.




39 inches

75 inches


54 inches

75 inches​


60 inches

80 inches


78 inches

80 inches

Table 1 - Standard Mattress Sizes

Variations in Standard Sizes

Just to confuse you further, you may encounter variations to the standard sizes shown in Table 1 above.

These variations may include:





39 inches

80 inches


72 inches

84 inches​

Variations also include:

  • Split queen or king. Split queen or king mattresses divide the width in half and consist of two mattresses contained within the same bed frame.
  • Custom mattress sizes. As the name suggests, some manufacturers will make mattress made to measure based on your specifications. Proprietary size mattresses may require custom bed frames and bedding provided by specialty suppliers.

Mattress size. Image Source.

How Do You Choose The Right Mattress Size?

The correct mattress size depends on 3 things:

  • The age and size of the person using it
  • Space available in the bedroom
  • Size of the bed frame.

Which Mattress Size Is Right For You?

Twin size mattresses

These are suitable for children's rooms and are the standard size mattress for bunk beds, trundle beds, and daybeds.

Twin XL mattresses

These provide extra comfort for older teens and tall adults. For this reason, twin XL is the preferred mattress size for use in college dormitory rooms.

Full, Queen. King and Cal King sizes

These sizes accommodate single adults or couples, although many couples prefer the extra room provided by king or California king size.

Queen Sized Mattress. Image Source.

When planning for the larger sizes, make sure the room is big enough to provide at least 18 inches of clear space between the edges of the bed and the walls or other furniture.

Split mattresses

These sized mattress have several uses.

Since two different composition mattresses can be placed in one bed frame, a split mattress allows a couple to choose different firmness levels to maximize individual comfort.

Split mattresses are also used in adjustable beds with mechanisms that raise or lower the foot or head of the bed.

Finally, split mattresses are used to reduce the weight of king and California king mattresses, allowing for easier transport in moving and delivery of the mattress.

Fitted Sheets For Your Mattress Size

Have a listen to Steve, the owner of VeroLinens, as he explains how to avoid getting the wrong fitted sheets for the mattress size you have decided to buy.


The common mattress sizes twin, full, queen, and king can accommodate most people's needs for sleeping comfort. These sizes are also standard bedding sizes, making it easy to shop for properly-fitting sheets, mattress pads, and blankets. The variations in mattress size, such as extra length and custom sizes, provide an even greater range of personal fit and comfort that's essential for a good night's sleep.

mattress size