Bed sizes are slightly different in the US than in the UK, so the equivalent US  bed sizes are here. Twin (UK single) 3 ft 3 inches wide X 6 ft 3 inches long Twin XL 3 ft 3 inches X 6 ft 8 inches long Small double three-quarter size 4 ft wide X 6 ft 3 inches long Full  (UK double) 4 ft 6 inches wide X 6 ft 3 inches long Queen (UK King) 5 ft wide X 6 ft 8 inches long King 6 ft 4 inches wide X 6 ft 8 inches long California king (UK super king) 6 ft wide X 7 ft long