If you're shopping for a new mattress, you might glance at some of the sizes (RV King?) and wonder if you should consider changing your Queen for a King. This mattress size guide includes a quick comparison between the most commonly available sizes and provides some information about who each size is best suited for. You can also read about when you should consider mattress height.
Standard Sizes
Most mattresses are available in a few standard sizes at a minimum, including Twin (75" X 38"), Twin XL/Long (80" X 38"), Full/Double (75" X 53"), Queen (80" X 60"), King (80" X 76"), and California King (72" X 84").
Twin and Twin XL mattresses are best suited for children and single adults who don't need much space to spread out. Twin XL mattresses are longer and can comfortably accommodate taller adults.
Full/Double beds are a good option for single people who want extra room to spread out, and can also work for couples who don't mind a slightly more cramped sleeping space. Queen-sized mattresses are ideal for many couples and can fit into more modest bedrooms compared with bigger formats. King and California King-sized mattresses leave ample room for couples and even pets or kids who sometimes jump into bed but require a lot of space. California King beds are a few inches longer compared with King-size beds, which might appeal if your dog curls up near your feet at night.
The most widely available type of split mattress is a Split King, where each side is equal to a Twin XL mattress.
It's worth noting that we test the Queen-sized variants of the mattresses we review. The same mattress can perform differently in different sizes. Here's a mattress dimensions chart covering standard mattress sizes.
| Standard Mattress Sizes | ||
|---|---|---|
| Size | Length | Width |
| Twin | 75"/191 cm | 38"/97 cm |
| Twin Long | 80"/203 cm | 38"/97 cm |
| Full/Double | 75"/191 cm | 53"/135 cm |
| Queen | 80"/203 cm | 60"/152 cm |
| King | 80"/203 cm | 76"/193 cm |
| California King | 72"/180 cm | 84"/213 cm |
Twin vs. Twin XL
Twin XL or Twin Long (80" X 38") mattresses have the same width as Twin mattresses (75" X 38") but are longer, at about 80" (around 6'67") in length. This size is a good option for single adults with limited space or for outfitting guest rooms with places for multiple people to sleep.
King vs. California King
If you're interested in sizes beyond King, most mattresses are also available in a California King size. California Kings are longer than standard King-size mattresses, but not as wide.
RV And Oversized Mattresses
The above sizes are the most widely available, but you'll also find many mattresses available in Short Queen (60" x 74") and RV King (72" x 80") sizes. These are narrower than standard Queen and King mattresses, respectively, and are meant to fit into trailers and RVs. Some additional 'oversized' mattress formats include Family Bed (144" x 84"), Alaskan King (108" X 108"), Alberta King (96" x 96"), Texas King (98" X 80"), and Wyoming King (84" X 84") mattresses.
Mattress Thickness
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Standard mattresses range from 8" - 12" in height, but mattresses up to 15" high are not uncommon. These are usually hybrid mattresses, which you can read more about in our guide to that mattress type. While thickness may seem like a lesser concern compared with your overall mattress size, it's worth considering for a few reasons.
Thicker mattresses (over 12") might require new sheets. Standard fitted sheets are meant for standard mattresses up to 12" high, so if your mattress is any taller, you may need deep-pocket fitted sheets. You can also use sheet suspenders, especially if your sheets fit but just barely. If you like your top sheet tucked in at the foot of your mattress, you might also need a bigger flat sheet if your mattress is thick. You can buy oversized flat sheets or just go for one size up.
Finally, if you have mobility issues or simply want to make sure getting in and out of bed is comfortable, it may be worth considering whether your mattress's height will make your bed lower or higher overall.
More Information
If you're just starting out in your mattress search, you might also want to check out our guide on how to choose a mattress. If you've already read a lifetime's worth of mattress shopping guides, get directly to the point with our picks for the best mattresses we've tested so far, or look at all of our mattress reviews.