A full-size bed, also referred to as a double bed, is 54 inches wide. Although it is significantly wider than the 39-inch twin bed, it does not give the same amount of room to two people sleeping on it as two twin beds would.
The standard full-size bed is 75 inches long, the same length as a standard twin but five inches shorter than the standard queen bed in length. The queen is also 6 inches wider than the full bed. Despite the difference in size, many comforters are made to fit either full or queen beds. The full/queen comforter is typically 86 by 86 inches.