California King

Twin or single - 39 inches x 75 inches = 99 cm x 191 cm = 3' 3'' x 6' 3''
Twin XL - 39 inches x 80 inches = 99 cm x 203 cm = 3' 3'' x 6' 8''
Three quarters - 48 inches x 75 inches = 122 cm x 191 cm = 4' x 6' 3''
Full or Double - 54 inches x 75 inches  = 137 cm x 191 cm = 4' 6'' x 6' 3''

US Queen or UK king - 60 inches x 80 inches = 152 cm x 203 cm = 5' x 6' 8''
US King or UK Superking - two twin xl - 76 inches x 80 inches = 193 cm x 203 cm = 6' 4'' x 6' 8''
Cal King - 72 inches x 84 inches = 183 cm x 213 cm = 6 foot x 7 foot

References;
* Mattress dimensions
* Bed size
* Bed sizes