Size Dimensions Notes Small Single 75 cm × 190 cm (30 in × 75 in) Common UK size for hospitality (zip & link) twin beds as beds can be combined to make a short king bed. Equivalent to previous 2’6″ x 6’3″ Buying a too-small mattress is one of the biggest mistakes new bed-buyers make. Couples who’ve been sleeping on a “double” (also known as a full-size mattress) since they got together may think they have enough room – until they learn that each person has only as much sleeping space as a baby’s crib! Buy Best Price Mattress 12-Inch Memory Foam Mattress, California King: Furniture – Amazon.com FREE DELIVERY possible on eligible purchases The bed sizes available in the United States are the twin, single, double, full, queen, king, California king, Western King, and Eastern King. .