US mattress sizes: Twin to California King
A US Queen is 60 by 80 inches, or 152.4 by 203.2 cm. The chart lists the six common sizes as published by the Better Sleep Council, the consumer education arm of the mattress industry association.
Last updated: September 28, 2026
US mattress size chart
Sizes are width by length of the mattress.
| Size | Width (in) | Length (in) | Width (cm) | Length (cm) |
|---|---|---|---|---|
| Twin | 38 | 75 | 96.5 | 190.5 |
| Twin XL | 38 | 80 | 96.5 | 203.2 |
| Full | 53 | 75 | 134.6 | 190.5 |
| Queen | 60 | 80 | 152.4 | 203.2 |
| King | 76 | 80 | 193 | 203.2 |
| California King | 72 | 84 | 182.9 | 213.4 |
How to use the chart
- Measure the inside of the bed frame, or the old mattress, in inches.
- Find the size with that width and length.
- Before you order, compare with the dimensions that the manufacturer states for the exact product.
If you are buying from outside the United States, use the centimetre columns to compare with local sizes. A US Queen is not the same as a UK King or a European 160 by 200 cm mattress.
Where manufacturers differ
These sizes are industry conventions, not law. The published values differ in two places.
- Full: the Better Sleep Council states 53 inches wide; Sealy states 54 inches.
- Length: the council and Sealy state 75, 80 and 84 inches; Serta states 74.5, 79.5 and 83.5 inches.
The differences are an inch or less. They matter when a mattress has to fit into a recess or an existing frame. In those cases measure the space and ask the seller for the actual dimensions.
How the sizes relate to each other
- Twin XL has the width of a Twin and the length of a Queen.
- Two Twin XL mattresses side by side are 76 by 80 inches, the size of a King. This is what a split King consists of.
- A California King is 4 inches narrower and 4 inches longer than a King.
- A Full is 15 inches wider than a Twin and has the same length.
Worked example: will a Queen fit?
A bedroom alcove is 158 cm wide and 210 cm deep. A Queen is 152.4 cm by 203.2 cm, so the mattress fits with 5.6 cm to spare in width and 6.8 cm in length.
A bed frame is larger than its mattress. Check the outer dimensions of the frame before you decide.
Common mistakes
- Assuming a King is the longest bed. A California King is longer; a King is wider.
- Buying Twin sheets for a Twin XL. The mattress is 5 inches longer.
- Ordering a US size for a frame bought in Europe or the United Kingdom. The sizes do not match.
- Forgetting the height of the mattress when buying fitted sheets. The chart gives width and length only.
Sources and checks
The values in the chart are the sizes published by the organisations listed below. Last checked against the sources on September 28, 2026.
Inch values are those of the Better Sleep Council. Centimetre values are conversions at 2.54 cm per inch, rounded to one decimal.
These are nominal sizes, not a legal standard. Manufacturers deviate: Full is listed as 53 or 54 inches wide, and some state lengths half an inch to one inch shorter.
The guideline of the industry association itself is sold as a document and was not read.
Used for: Width and length in inches of Twin, Twin XL, Full, Queen, King and California King. The council is the consumer education arm of the International Sleep Products Association.
Used for: Second reference. Agrees with the council except for Full, which it lists as 54 inches wide.
Used for: Example of a manufacturer that states lengths half an inch shorter, such as 74.5 and 79.5 inches.
Frequently asked questions
- What are the dimensions of a Queen mattress?
- A US Queen is 60 inches wide and 80 inches long, which is 152.4 cm by 203.2 cm.
- Is a US Full the same as a UK double?
- Nearly. A US Full is 53 by 75 inches, which is 134.6 by 190.5 cm. A UK double is 135 by 190 cm. The difference is smaller than the deviation manufacturers allow themselves.
- What is the difference between King and California King?
- A King is 76 by 80 inches. A California King is 72 by 84 inches: 4 inches narrower and 4 inches longer.
- How long is a Twin XL?
- A Twin XL is 38 by 80 inches, or 96.5 cm by 203.2 cm. It is 5 inches longer than a Twin.
- Is a Full 53 or 54 inches wide?
- Both values are published. The Better Sleep Council states 53 inches and Sealy states 54 inches. Check the dimensions of the product you are buying.