What You Should Know About Bed Comforter Sizes

Illustration depicting comforter measurements
Illustration: Catherine Song. © The Spruce, 2018 

Buying the right comforter size for your bed can be harder than you imagine because the specifications offered by comfort manufacturers may not match up exactly—or even acceptbly—to your mattress.  Matching a comforter to a queen-sized bed can be particularly vexing, in part because some manufacturers view double (full) and queen comforters as being interchangeable, while other manufacturers do not.

Unfortunately, it's not unusual to purchase a comforter, only to then find it's too small (most common) or too large (less common) for your particular mattress. 

Comforter Sizes Vary Widely

Although mattress sizes are standardized, comforter sizes are not:

Bed Mattress Measures ** Standard Comforter Widths
(in Inches)
Standard Comforter Lengths
(in Inches)
Crib 28" x 52" 28" to 36" 46" to 52"
Twin 39" x 75" 66" to 68" 86" to 88"
Double/Full 60" x 80" 81" to 84" + 86" to 88"
Queen 60" x 80" 86" to 88" 96" to 100"
King (Standard/Eastern) 76/78" x 80" 102" 86" to 88"
California King 72" x 84" 107" to 110" 96" to 98"

These sizes are only guidelines, and it's common for some manufacturers to either add a few extra inches or shave inches off of these "standard" sizes. Be especially careful about very fluffy comforters, such as those filled with down. These tend to puff out the fabric, so there is even less coverage than the dimensions listed on the package.

Matching a Comforter to Your Mattress

The standard categories offer a starting point for selecting a comforter that matches your bed mattress. If you have a twin-sized mattress, for example, you'll want to purchase a comforter labeled as such. Likewise, if you have a king-sized mattress, purchase a king-sized comforter. But within each category, comforters come in a range of lengths and widths, and here is where you need to pay attention to the thickness of your mattress. If your own mattress is on the thick side, you'll need to look for a comforter at the top range of the dimension range—or in some cases, you might even jump up to the next category. 

Choosing the right comforter size tends to be trickiest with a full-sized or queen-sized bed since manufacturers often confuse their sizing standards by claiming their comforters are sized for both sizes. In practice, if you purchase a queen comforter labeled for a full/queen bed for your full-sized bed, you may find its edges fall closer to the floor than you wish.

On the other hand, if you have a queen-sized bed and you purchase a comforter labeled as full/queen, you may find that it is not quite wide enough to cover your bed adequately. In this case, you may want to shop specifically for the queen comforter size, or at least make sure the full/queen comforter you're considering is on the wider side (86" to 88", rather than 84").

Some of this may depend on the thickness of your mattress, as well. If you have a particularly thin bed—a futon or something like it—you probably can get away with a narrower comforter, since you'll need less of it to cover the sides of your bed. On the other hand, newer pillow-top mattresses can be as deep as 14" to 16", and here you'll need a considerably wider comforter to cover the sides of the mattress completely.

One good way to approach this is with simple measurements: take the top dimension of your mattress and add the thickness of the mattress to the length and to each side of the comforter dimensions. This should ensure that the comforter drapes down fully over the end and sides of the mattress. For example, a twin bed mattress that is 39 inches wide and 75 inches long and 12 inches thick, will need a comforter that is 63 inches wide (12 inches on each side) and 87 inches long in order to fully cover the sides and the bottom end of the mattress. A few extra inches might be even better, especially if the comforter is on the puffy side.

Mattress thicknesses vary widely by manufacturer, although thicker mattresses are far more common than they were a few years ago. Standard and older mattresses average between 9" and 12" deep, which means they'll work with most standard comforter sizes. But newer pillow-top mattresses may be as thick as 20 inches, which will call for a considerably larger comforter. 

Oversized Comforters

Due to the recent popularity of thick, pillow-top mattresses, some manufacturers are offering "oversized queen" and "oversized king" comforter sizes in addition to their standard sizes. These comforters have more width for their length: in the case of queen comforters, they're usually around 98 inches wide, and in the case of king comforters, they're usually around 115 inches wide. If you want a wide comforter but don't want to jump up to the next standard size, these may represent a good compromise.

It is generally fine for the comforter to be slightly oversized so it hangs below the bottom of the mattress. The space between the bottom of the mattress and the floor is often covered with a bed skirt or ruffle, and it is visually more pleasing for the comforter to overlap the skirt than for it to fall short.