A king size mattress in the United States typically measures 76 inches wide by 80 inches long. This size is the widest standard mattress size available and provides ample space for couples or individuals who want extra sleeping area. The recommended room size for a king mattress is at least 12 feet by 12 feet to accommodate the bed comfortably. In metric terms, this is approximately 193 cm wide by 203 cm long. King mattresses offer a spacious and luxurious sleeping surface, ideal for couples or those who sleep with children or pets.
