Are 2 Twin Mattresses the Same Size As 1 King Size Mattress?

U.S. Standard Twin and King Beds

• Standard twin bed mattresses in the United States measure 39 inches wide by 75 inches long. Standard king beds measure 76 by 80 inches. Exact measurements may vary with a particular manufacturer or model. If you push two standard twin beds together, you get a combined area 78 inches wide and 75 inches long. This is 2 inches wider and 5 inches shorter than a standard king bed.

U.S. Twin Extra-Long and Standard King

• A twin extra long bed measures 39 inches wide by 80 inches long. Combining two of these, you get a sleep surface 78 inches wide and 80 inches long. The result still measures 2 inches wider than the standard king, but it has the same length. You can also purchase a pad or bridge to even out the crack between the two mattresses. A king sized flat sheet tucked in or a fitted bottom sheet with sufficient give can cover both mattresses and give the appearance of one bed.

California King

• A California king bed is narrower and longer than a standard king. It measures 72 inches wide by 84 inches long. Two twin extra-long beds pushed together, measuring 78 inches wide by 80 long, are 6 inches wider than a Cal king and 4 inches shorter. Two regular twin beds have the same difference in width and measure 9 inches shorter. Neither regular nor extra-long twin beds make a close substitute for a California king.

Sizes in Other Countries

• Bed sizes in Canada are similar to those in the U.S., but many other countries have different sizes. In Australia, a single bed measures 36 inches wide by 74 inches long, and a single extra long measures 36 by 80. Two Australian single extra-long beds pushed together have the same size as an Australian king, 72 inches wide by 80 inches long. In the United Kingdom, a single bed measures 35 inches wide by 75 inches long. Two pushed together equal 70 by 75. This size doesn't exactly match either a U.K. king, at 60 by 78, or a super king, at 72 by 78.