Mattress Sizes: The Complete Dimensions Chart

There are six standard mattress sizes in the United States: twin (38" x 75"), twin XL (38" x 80"), full (54" x 75"), queen (60" x 80"), king (76" x 80"), and California king (72" x 84"). Queen is the most common size for couples, king is the widest, and California king trades four inches of width for four inches of length. Everything else you'll see on a showroom floor — split king, full XL, Olympic queen, Wyoming king — is a variation built off those numbers.

Mattress sizes chart: standard dimensions

These are the standard measurements used across the U.S. mattress industry. Manufacturing tolerances mean an individual mattress can run about half an inch off in either direction — enough to matter for a tight bed frame, not for sheets.

The six standard mattress sizes explained

Twin: 38" x 75"

The smallest adult size and the default for kids' rooms, bunk beds, and trundles. At 75 inches long it's tight for anyone over about 5'8", since you want a few inches of clearance past your feet. Two twins side by side span 76 inches — the same as a king — which makes them a practical way to furnish a shared kids' room.

Twin XL: 38" x 80"

Same width as a twin, five inches longer. That extra length matches a queen and a king, so a twin XL fits tall teens and single adults without using more floor space. Two twin XLs together equal a king, which is what makes split king setups possible. Browse twin XL mattresses to see the range.

Full: 54" x 75"

Also called a double. A full is 16 inches wider than a twin but no longer, so it's roomy for one adult and cramped for two — each person gets 27 inches, narrower than a crib. Fulls suit guest rooms, studios, and bedrooms where a queen would block a doorway or closet.

Queen: 60" x 80"

The most popular mattress size in the country, and the one most bedding, frames, and headboards are designed around first. At 60 inches wide, each person in a couple gets 30 inches — about a crib mattress each. For most bedrooms it's the best balance of sleeping room and floor space. See the full range of queen mattresses.

King: 76" x 80"

Sometimes called an Eastern king. Sixteen inches wider than a queen, same length — 38 inches per person, twin-width each, which matters if one of you moves a lot at night or a kid or dog ends up in the bed. It needs a wide room and doorway, and a king boxspring usually ships as two halves because a single 76-inch piece won't make it up most staircases. Shop king mattresses for the options.

California king: 72" x 84"

A common misconception is that a California king is bigger than a king. It isn't — it's four inches narrower and four inches longer, and a king actually has slightly more total surface area. Choose a Cal king if height is the constraint: at 84 inches, it's the only standard size that comfortably fits sleepers around 6'4" and up. Note that Cal king sheets, frames, and protectors are a separate size and won't fit a standard king.

Split and oversized mattress sizes

Split king and split California king

A split king is two twin XL mattresses used as one bed; a split California king is two 36" x 84" halves. Both exist so each person can pick their own firmness and each side can move independently on an adjustable base. The trade-off is a seam down the middle and the need for two twin XL fitted sheets or a dedicated split king set.

Olympic queen, Wyoming, Texas, and Alaskan king

These are specialty sizes from a limited number of manufacturers: Olympic queen is 66" x 80", Wyoming king 84" x 84", Texas king 80" x 98", and Alaskan king 108" x 108". All require custom or special-order bedding and frames, so confirm availability and lead time before committing.

How to pick the right mattress size

Three things decide it: who's sleeping on it, how tall they are, and what the room can take.

• Measure the room first, not the bed. A useful rule of thumb is to leave about two feet of clear floor on every side you need to walk past. For a queen that means roughly a 10' x 11' room; a king or Cal king is comfortable from about 12' x 12'.
• Add your height plus about 4 inches. If that beats 75 inches, skip twin and full for the 80-inch sizes (twin XL, full XL, queen, king) or an 84-inch California king.
• Check the path, not just the room. Doorways, stair landings, and tight hallway turns are what actually stop a king from being delivered. Measure the narrowest point on the route.
• Price in the bedding. Moving up a size usually means new sheets, a protector, a comforter, and often a new frame — and almost nothing from a standard king carries over to a Cal king.
• Going on an adjustable base? Split sizes and adjustable bases need to be matched as a set, so decide on the base and the mattress size together rather than one after the other.

Thickness is not part of the size name

"Queen" tells you width and length only. Thickness varies independently, commonly from around 8 inches on a basic foam model to 14 inches or more on a thick hybrid. Fitted sheets are sold by pocket depth, and most standard ones stop fitting somewhere around 15 inches, so a tall mattress may need deep-pocket sheets. Thickness also changes how high the bed sits on a frame or base.

Frequently asked questions

What is the most common mattress size?

Queen, at 60" x 80". It's the size most couples buy and the one bedding and bed frame manufacturers design for first, which also makes it the easiest size to shop for accessories.

Is a California king bigger than a king?

Not in width. A California king is 72" x 84" and a standard king is 76" x 80", so the Cal king is four inches narrower and four inches longer. A standard king has a slightly larger total sleeping surface; the California king is the better pick purely for tall sleepers.

Do two twin XL mattresses make a king?

Yes. Two twin XL mattresses measure 76" x 80" side by side, exactly a standard king, which is how split king beds work. Two standard twins also come to 76 inches wide but only 75 inches long, so they make a king-width bed that's five inches short.

What size mattress fits a 10x10 bedroom?

A queen is usually the largest comfortable choice in a 10' x 10' room, and a full gives you noticeably more floor space. A king fits physically but leaves little room to walk around the foot of the bed or open a closet door, so measure where the bed will actually sit before deciding.

Can I use queen sheets on a full mattress?

Not well. A full is 54" x 75" and a queen is 60" x 80", so queen sheets will be loose and bunch under you. Buy bedding to the exact size — Cal king, full XL, and twin XL all have their own dimensions.

See the sizes in person in Glendale

Dimensions on a chart only go so far — the difference between a queen and a king is something you feel when you lie down, not something you read. Our Glendale showroom has the standard sizes set up so you can compare them side by side, and we can tell you what's in stock in each size.

Every mattress comes with a 120-night sleep trial, so you have real time at home to find out whether you sized it right. We also offer free delivery and setup across the Los Angeles area, a 90-day price match, and 0% APR financing. Come in, or start with the full mattress collection.