Duvet for double bed. This duvet is 225 cm x 220 cm (89 inches x 87 inches) and will fit a bed of 150 cm x 200 cm (5ft x 6ft 6 inches). Check Most Popular. King size duvet. Duvet for king size bed. This duvet is 225 cm x 220 cm (89 inches x 87 inches) and will fit a bed of 150 cm x 200 cm (5ft x 6ft 6 inches).