Minecraft Slime Chunk Finder

Slime chunks are 16 × 16-block chunks where slimes spawn below Y 40, regardless of light level. About one in ten chunks is a slime chunk. In Java Edition, this depends on the seed; in Bedrock Edition, it depends only on the chunk coordinates.

The quickest way is with this Slime Chunk Finder: choose your edition, enter the seed for Java, and enter your X and Z position. The map marks all slime chunks in green, while the list shows the ten nearest ones with their distance, direction, and coordinates. Without a tool, you can only experiment: excavate an area below Y 40, light up the surroundings, and wait to see whether slimes spawn there. This often takes hours and is unreliable.

No, F3 does not show slime chunks without mods. In Java, F3 does show your coordinates and the chunk you’re standing in; in Bedrock, “Show Coordinates” shows your position. Enter X and Z here and click “Jump To”: the Slime Chunk Finder selects the chunk at your position and shows whether it’s a slime chunk, along with its X and Z block ranges. In Java, F3 + G also displays chunk borders.

In Bedrock Edition, yes: Bedrock calculates slime chunks solely from chunk coordinates, so they occur in the same places in every Bedrock world, and Bedrock mode needs no seed. In Java Edition, the seed and chunk coordinates determine the slime chunks; without a seed, the tool cannot show any. The /seed command shows your seed in chat. On your own server, you can find it in server.properties under level-seed. If you created the world using text as the seed, simply enter that text: the tool converts it to a number just as Minecraft does.

In slime chunks, slimes spawn below Y 40 regardless of light or weather, so you can light up your spawning platforms. They also spawn in swamps and mangrove swamps between Y 51 and Y 69 when the light level is 7 or lower. Spawn rates there depend on the moon: highest at a full moon and zero at a new moon. For Java worlds, the Slime Chunk Finder displays these biomes as a swamp layer.

At the AFK point calculated by the Farm Spot Finder. It checks possible AFK points every four blocks within your chosen search radius and evaluates how much slime chunk area falls within your edition’s spawning range: 24 to 128 blocks in Java, or 24 to 44 blocks in Bedrock (default simulation distance of 4). Distances are calculated horizontally, so stand at the height of your spawning platforms. Dig out the slime chunks below Y 40, build several spawning platforms with about three blocks of air between them, and light up nearby caves so other mobs don’t occupy the spawning spaces.

Common reasons: the difficulty is set to Peaceful; you're closer than 24 blocks or beyond spawning range (128 blocks in Java, about 44 blocks in Bedrock); the area is above Y 40; or there isn't enough room, as large slimes need just over two blocks of height. Other monsters in unlit caves can also fill the mob cap. Check that you've selected the right edition and entered the correct seed, too.

The Slime Chunk Finder is free and requires no sign-up. The map, Farm Spot Finder, and swamp layer (via WebAssembly) run locally in your browser. Your seed does appear in the address bar so reloading or bookmarking preserves your view: if you reload the page using that address or open a bookmark, the address, including the seed, is sent to our server. In Java, the link created by “Copy Link” also contains your seed, along with your position, zoom level, and selected chunk.