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 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. The outer two chunks of the usable world is usually a smooth transition from the main landmass/noise generation to the sea of water. 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 and generated structures available in the current version. The tile on each edge of the Overworld and Nether is inaccessible, so the effective area is 2 tiles less on both axes.

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 are overwritten by newly generated tiles to make the world size increase seamlessly. When disabled, the world size increase will leave all original tiles intact." Starting with a smaller world can be beneficial, as one may choose to gradually expand when an update makes changes to the world generation, and could therefore generate new chunks with 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 are 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 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. 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.

History
世界大小