Bed Size Guide Tool

Please enter a room length and width greater than 0.

Assumes the head of the bed is against a wall and you leave the chosen space on both sides and at the foot. Also check doors, wardrobes and other furniture.

How to use this tool

Enter your room length and width in feet and choose how much walking space you want around the bed. Press the button to see which mattress sizes fit. The table below shows the standard US mattress sizes.

Mattress size chart

Size Inches (W x L) Centimeters Best for
Twin 38 x 75 97 x 191 Children, small rooms
Twin XL 38 x 80 97 x 203 Tall single sleepers, dorms
Full 54 x 75 137 x 191 One adult, guest rooms
Queen 60 x 80 152 x 203 Couples, most bedrooms
King 76 x 80 193 x 203 Couples who want more space
California King 72 x 84 183 x 213 Tall sleepers

Example: A 10 ft × 10 ft room with 24 inches of space around the bed fits up to a California King. A King is too wide.

How to choose the right mattress size for your room

The mattress size chart lists the six standard US sizes, and the room checker shows which ones fit your bedroom with comfortable walking space. A bed that fits on paper can still feel cramped. The clearance you choose decides how easy it is to move around, open drawers and make the bed.

What decides the best size

  • Who sleeps in the bed. Couples usually need a Queen or larger. A single adult may be fine in a Full or Twin XL.
  • Sleeper height. People over about 6 feet often prefer 80 inch or longer beds, such as a Twin XL, Queen, King or California King.
  • Room size. The bed should leave room for walking on both sides and at the foot.
  • Other furniture. Nightstands, dressers and doors take space that the bed cannot use.

Two examples

A 10 by 10 foot room is 120 inches each way. With 24 inches of clearance on both sides, the bed can be up to 120 − 48 = 72 inches wide. That fits a California King at 72 inches wide but not a King at 76 inches. A Queen at 60 inches leaves extra room for nightstands.

In a 12 by 12 foot room with 30 inches of clearance, the bed can be up to 84 inches wide and 114 inches long. A King at 76 by 80 inches fits easily.

Tips and common mistakes

  • Measure the bed frame, not just the mattress. Frames and headboards can add several inches in each direction.
  • Check doors, stairs and hallways. A large mattress or box spring must fit through them to reach the room.
  • Leave space for dresser drawers and closet doors to open fully.
  • Do not buy the largest size that fits if it leaves no room to walk.

Buying advice

Remember that a bigger mattress also means bigger sheets, comforters, frames and protectors, which add to the total cost. Queen bedding is the most widely available. If you share a bed and sleep differently, a King or a split King made from two Twin XL mattresses can reduce motion transfer. Check the store’s return or trial policy before you buy.

Frequently asked questions

What are the standard mattress sizes?
Twin, Twin XL, Full, Queen, King and California King. A Queen is 60 by 80 inches and a King is 76 by 80 inches.
What is the difference between King and California King?
A King is wider (76 inches) and shorter (80 inches). A California King is narrower (72 inches) and longer (84 inches).
What size room do I need for a queen bed?
A room of about 10 by 10 feet is a comfortable minimum for a queen bed with a nightstand and walking space.
How much space should I leave around a bed?
Leave at least 24 inches on the sides and at the foot so you can walk around and make the bed easily.
Which mattress size is best for two people?
Most couples choose a Queen or King. A King gives each person about the width of a Twin XL bed.
Is a full bed the same as a double?
Yes. In the US, a full and a double are the same size, about 54 by 75 inches. The name double comes from it once being the standard bed for two people. Today, most couples choose a Queen or larger, while a full suits one adult or a guest room.
What is a split king?
A split king is two Twin XL mattresses placed side by side. Together they measure about 76 by 80 inches, the same as a standard King. Couples choose it to use different firmness levels or adjustable bases on each side. It needs Twin XL fitted sheets but can use one king top sheet and comforter.
How thick should a mattress be?
Most adult mattresses are about 8 to 14 inches thick. Thicker mattresses often have more comfort layers, but thickness alone does not mean better quality. Consider your weight, sleep position and bed height. A very thick mattress may need deep-pocket sheets and can make the bed hard to get into.