Here’s a nice little find at Wikipeida:
An overlay diagram showing four of the largest airplanes ever built, the Hughes H-4 Spruce Goose (aircraft with the greatest wingspan), the Antonov An-225 Mriya (the largest aircraft), the Boeing 747-8 Intercontinental (soon to be the largest version of the Boeing 747 Jumbojet), and the Airbus A380-800 (the largest passenger aircraft).
Despite current notions, sdize does not matter – payload does. What are the working payloads for these three monsters?