Mattress Sizes & Dimensions

Standard US mattress dimensions (width × length) are:

• Twin: 38 × 75 in
• Twin XL: 38 × 80 in
• Full (double): 54 × 75 in
• Queen: 60 × 80 in
• King: 76 × 80 in
• California king: 72 × 84 in

Actual sizes can vary slightly between brands. Two twin XLs side by side make a king surface, which suits split-firmness and adjustable bases.

When choosing a size, leave walking space around the bed (around 24 to 30 in is a common guideline), measure stairways and doorways for delivery, and remember that mattress thickness affects sheet fit: deep-pocket sheets suit thicker mattresses. Taller sleepers often prefer a twin XL or California king for the extra length. Specialty sizes such as RV short queen and Olympic queen are covered in RV and specialty mattresses.