- The standard length of a twin mattress is 75 inches.
- Most twin mattresses are 38 or 39 inches wide.
- There is the most variation in the height of twin mattresses. Depending on construction, they are usually between 6 and 18 inches high. Foam mattresses are generally shorter than spring mattresses.
- A slight variation of the twin mattress is the twin XL. It is 80 inches long.
- A standard 38" by 75" twin mattress is approximately 99 by 191 in centimeters.







