Minecraft Dimension

Dimension Definitions

This content applies only to Java Edition.

Dimension definition files are the data-driven definitions of dimensions in datapacks.

Definition format

Dimensions use the LEVEL_STEM registry; the datapack path is dimension (definitions in data/<namespace>/dimension, tags in data/<namespace>/tags/dimension).

Definition files use JSON with the following structure:

• JSON file root object
  • type (string/compound, required): dimension type; inline definitions are parsed but fail datapack verification (no namespace ID) and interrupt connection.
  • generator (compound, required): chunk generator.
    • type (string, required): chunk generator type; extra fields per type (below).

Chunk generators

The chunk generator decides how terrain generates, plus the dimension's sea level, min build height, and total height. Noise generators read these from noise settings; the other two hardcode min height 0 and height 384 (flat sea level −64, debug 63).

• debug: generates the debug mode grid of blocks; no other terrain; fixed plains biome.
• flat: generates superflat worlds. settings (compound, required): flat generator settings.
• noise: generates complex terrain with a noise generator. Fields:
  • biome_source (compound, required): biome distribution (below).
  • settings (string/compound, required): noise settings.

Biome sources

Only noise generators can set a biome source; others use a fixed source.

• checkerboard: places biomes in a checkerboard. biomes (string/list, required: ID, tag, or list), scale (int, 0≤v≤62, default 2; each increment doubles the cell size; 0 = one chunk per cell).
• fixed: always uses one biome. biome (string, required).
• multi_noise: places biomes by biome noise; used by the Overworld and Nether. Either preset (string/compound, required) referencing a parameter list, or a non-empty biomes list of parameter points, each biome (string, required) + parameters (compound, required).
• the_end: used by the End dimension.

Multi-noise parameter lists

Stored in data/<namespace>/worldgen/multi_noise_biome_source_parameter_list; root object: preset (string, required): a biome parameter (vanilla provides overworld and nether). These lists only reference hardcoded parameters; vanilla uses them to temporarily modify Overworld biome distribution for experimental biomes.

Definition behavior

Dimension data is loaded only once at server startup; /reload does not reload it — a server restart is required. All available dimensions load dynamically when the save loads; disabling the providing datapack removes the dimension (adding/removing dimensions after world creation is discouraged — it may corrupt saves). Vanilla defines no dimension files; it registers dimensions via world presets, but dimension files override world preset definitions.