Minecraft slime chunk finder: Java and Bedrock

How to find slime chunks

Choose Java or Bedrock. Their slime chunk patterns differ.
Enter your world seed for Java. Java seed text is also accepted and converted to its decimal seed. In Bedrock, the slime grid is the same for every seed, so you can leave the seed at 0.
Enter your position as Block X and Block Z, then choose Show slime chunks.
Look for green squares marked S. The cross marks the chunk containing your position, and north is up.
Open the result in the seed map to see the slime overlay beside biomes and other map layers. The link names the generation version it opens; choose your world's generation version on the map.

The checker classifies 81 chunks, four chunks in each direction from your position plus the center. It does not search an entire world or inspect blocks in your save.

Block coordinates and chunk boundaries

A chunk is a 16 × 16 block column. Divide each block coordinate by 16 and round down to get its chunk coordinate. Negative values round toward the smaller number: Block X −1 belongs to chunk X −1, not chunk 0.

Examples for either the X or Z axis
Block coordinate	Chunk coordinate	Blocks in that chunk
0 to 15	0	0 to 15
16 to 31	1	16 to 31
−16 to −1	−1	−16 to −1
−32 to −17	−2	−32 to −17

The form takes block coordinates. The squares and result label show chunk coordinates, so do not enter a chunk coordinate as if it were your position in blocks.

Green slimes on flat grass inside a yellow chunk-border outline seen from above — Slimes in a slime chunk, chunk borders on. Looking straight down from 26 blocks above a superflat world with chunk borders shown (F3+G). The small yellow square on the grass is the outline of chunk -5, 3 (blocks -80 to -65, 48 to 63), a slime chunk; the lines running out to the edges are the walls of the same chunk seen in perspective. Five slimes are inside it. When we photographed it, the game listed 49 slimes in the loaded area; by our slime chunk finder (the same isSlimeChunk code the site uses) 41 stood in slime chunks, and the other 8 were all within 6.3 blocks of a slime chunk edge, where slimes hop after spawning. A recount after the pictures gave 41 of 50, with every outlier within 4.4 blocks of a slime chunk. Java 26.3, seed 28462718234064871, default superflat preset, easy difficulty, creative player hovering so that mobs can spawn. Nothing was placed or summoned. In-game screenshot taken by SeedLookout in Java 26.3. © 2026 SeedLookout.

Slimes inside the yellow and blue chunk-border walls of one chunk on a superflat world — The same slime chunk from one corner. From nine blocks up at one corner of slime chunk -5, 3, looking across it: the yellow and blue grid lines are its chunk borders (F3+G), and four slimes are inside. The slimes far off in the distance are in other slime chunks. When we photographed it, the game listed 49 slimes in the loaded area; by our slime chunk finder (the same isSlimeChunk code the site uses) 41 stood in slime chunks, and the other 8 were all within 6.3 blocks of a slime chunk edge, where slimes hop after spawning. A recount after the pictures gave 41 of 50, with every outlier within 4.4 blocks of a slime chunk. Java 26.3, seed 28462718234064871, default superflat preset, easy difficulty. Nothing was placed or summoned. In-game screenshot taken by SeedLookout in Java 26.3. © 2026 SeedLookout.

Java and Bedrock slime chunks

Java slime chunks depend on the exact world seed and chunk coordinates. Bedrock uses a different calculation based on chunk coordinates alone. Changing a Bedrock seed keeps this grid the same, although the terrain and biomes around it can change.

Slime chunk classification has no generation-version selector here. The full seed map still needs the correct generation version for the surrounding biomes and structures. A green square is a calculated slime chunk, separate from game verification of a farm or a published seed.

Before building a slime farm

Slime chunks identify places where underground slime spawning can occur below Y 40. The spawn position must be below that height; a green chunk does not make every floor inside it suitable.

Check the space around the spawning area, nearby hostile mobs, difficulty and your distance from the farm. These conditions affect whether slimes actually spawn. This checker does not measure them, predict farm rates or confirm that a location works in your server's settings.

Swamp slime spawning follows separate biome and spawning conditions. A swamp can support slimes without being a slime chunk, and a slime chunk does not have to be in a swamp. Use the biome finder if you are looking for swamp terrain.

For the spawning rules and farm designs, read the Minecraft Wiki’s Slime reference and slime farming tutorial.

Slime chunk finder FAQ

Do I need the seed in Bedrock?

No, the Bedrock slime chunk pattern does not depend on it. Leave 0 in the seed field to check the grid, or enter your world's seed if you want the seed map to show the surrounding world correctly.

Why are no slimes spawning in a green chunk?

Check that you selected the right edition and entered block coordinates. In Java, also check the seed. Then check spawning height, space, player distance, difficulty and competing hostile mobs. The chunk calculation alone does not establish that your farm can spawn slimes.

Can I search a larger area?

Choose Open in seed map after checking a location. The link keeps your checked seed, edition and block position, with the slime overlay selected. Pan or zoom there to inspect farther away; zoom in if the map says the slime overlay is hidden at its current scale.

Can I find a Java seed with several adjacent slime chunks?

Use Slime seed search in the world tools. It searches Java seeds for a chunk pattern you choose. This page checks chunks in a seed you already have.