/fillbiome Command Generator
BetaPick two corners and a biome, and the preview paints the new biome over a top-down map in the 4×4 cells the game really uses. Add a filter to only change one biome.
Describe it — AI writes the command
Type what you want in plain words. The AI fills the form below, so you can see it and change anything. It follows the edition and version you picked.
Checking the AI…
Paste a command— edit it here or move it to another version
33 × 17 × 33 = 18,513 blocks (limit 32,768). Biomes are 3D: cover the full height if caves below should change too.
Your command · Java 26.3
58 characters/fillbiome ~-16 ~-8 ~-16 ~16 ~8 ~16 minecraft:cherry_grove
- Biomes change in 4×4×4 cells, so the edges snap to the cell grid.
Raw editor
How it works
/fillbiome came in Java 1.19.3. It changes the biome in a box but leaves the blocks alone, so you see the difference in grass and leaf colour, water colour, which mobs spawn, and whether it rains or snows.
fillbiome ~-16 ~-8 ~-16 ~16 ~8 ~16 minecraft:cherry_grove fillbiome ~-32 -64 ~-32 ~32 320 ~32 minecraft:snowy_plains replace minecraft:plains fillbiome ~-16 ~-16 ~-16 ~16 ~16 ~16 minecraft:mushroom_fields replace #minecraft:is_forest
4×4×4 cells
The game stores biomes in cells of 4×4×4 blocks, not per block. The change snaps to that grid, so edges can look a few blocks off from the corners you typed. Biomes are also 3D: to change caves underneath, include them in the height.
The block limit
The box can hold at most 32,768 blocks. From Java 1.19.4 that is the commandModificationBlockLimit game rule (max_block_modifications from 1.21.11). A 64 × 384 × 64 column is far over it, so the generator splits big boxes into several commands that each fit.
Bedrock
Bedrock has no /fillbiome. The generator only writes Java.
FAQ
Does /fillbiome change the blocks?
No. Grass stays grass and sand stays sand. Only the biome changes, which affects grass and foliage colour, water colour, mob spawns, and rain or snow.
Why does the biome edge not match my coordinates?
Biomes are stored in 4×4×4 cells, so the game changes whole cells. Line your corners up with multiples of 4 for clean edges.
How do I only replace one biome?
Add a filter: fillbiome <from> <to> <biome> replace <old biome>. A biome tag like #minecraft:is_forest works too and catches every forest type.
Why does /fillbiome say too many blocks?
The box is over 32,768 blocks. Raise the game rule on Java 1.19.4+ or let the generator split the area into several commands.
Is there /fillbiome on Bedrock?
No. On Bedrock you would need a world editor to change biomes.