World size

World Size is an option to change the size of the finite worlds in New Nintendo 3DS Edition and Legacy Console Edition (specific to PlayStation 4 Edition, Xbox One Edition, and Nintendo Switch Edition). By default, worlds will generate at the largest size available in each edition.

Legacy Console Edition
In the finite worlds of Legacy Console Edition, the edge of the Overworld is surrounded by an endless sea of water preceded by an invisible barrier, and the edge of the Nether is surrounded by a wall of bedrock. The End is not affected by world size. Worlds are able to generate with any of the biomes (albeit at a reduced size) and generated structures available in the current version.

After a world has been created, it can be expanded to a larger size. Larger worlds cannot be reverted to a smaller size. In this process, there is an option to "Overwrite World Edges", disabled by default. The description of this option reads: "When enabled, the outer 32 tiles around the world edge will be overwritten by newly generated tiles to make the world size increase seamless. When disabled, the world size increase will leave all original tiles intact." Creating a smaller world can be beneficial; especially in the PlayStation 4 Edition, because after an update makes changes to the world generation, the old world can be expanded to generate new chunks with the new features.

Xbox 360 Edition, PlayStation 3 Edition, PlayStation Vita Edition, and Wii U Edition do not have the option for world size. All worlds generated in these editions will be at Classic size, although it is possible to expand them if they are transferred to an edition that supports larger world sizes. More villages, ocean monuments, and woodland mansions will attempt to generate in Classic than in larger-sized worlds.

New Nintendo 3DS Edition
The finite worlds of the New Nintendo 3DS Edition are based on the Old world type from Bedrock Edition. The edges of both the Overworld and Nether are surrounded by an invisible barrier, and the ratio of the Nether to the Overworld is 1:3 regardless of world size. It is not possible to change the size of a world after it has been created.