Minecraft Spawn Chunk Calculator
By the ChunkScan Team · Updated October 2026
Quick answer: To see your spawn chunks, type the X and Z of your world spawn (or paste F3 + C) and the page lists each ring as a block range. Since Java 1.20.5 their size is the spawnChunkRadius game rule, 2 by default. Example: with spawn at 48, -120 and the default radius 2, everything runs in X 48 to 63, Z -128 to -113. Link a result with /spawn-chunk-calculator?x=48&z=-120.
Type the X and Z of your world spawn and this calculator shows which chunks the game keeps loaded round it, as block ranges for each ring: where everything runs, where only blocks tick and where chunks stay loaded but frozen. Use the default radius, your own spawnChunkRadius or the fixed size of 1.20.4 and older, and type a farm's X and Z to see which ring it is in. Java Edition only; Bedrock has no spawn chunks.
What are spawn chunks?
On Java Edition the server keeps a square of chunks around the world spawn loaded, even when no player is near. Farms built there keep working while you are on the other side of the world, which is why iron farms, mob switches and item sorters often sit at spawn. The square has three rings: in the middle everything runs, in the next ring only blocks tick (redstone, crops, furnaces), and the outer ring is loaded but frozen.
How big are they?
Since Java 1.20.5 the size is the spawnChunkRadius game rule, 2 by default. With 2, one chunk runs everything, a 3 × 3 square runs redstone and crops, and a 5 × 5 square stays loaded. Raise it with the game rule (up to 32) on your own world or server; 0 turns spawn chunks off. In 1.20.4 and older the area was fixed and much larger: 19 × 19 chunks for entities, 21 × 21 for block ticks and 23 × 23 loaded. Bedrock Edition has no spawn chunks; use a ticking area there instead.
How to use this calculator
Pick your version, type the radius if you changed it, then type the X and Z of your world spawn, or paste an F3 + C line there. New players appear at world spawn; the seed map marks it on scanned seeds, and /setworldspawn moves it. The page lists each ring as a block range you can mark out in game. Type your farm’s X and Z to check which ring it is in, and use “Link to this result” to share it with your server.
Why doesn’t my farm run at spawn?
Mob farms need the middle ring, which is a single chunk with the default radius, and mobs still only spawn within 128 blocks of a player. Redstone clocks and crop farms need the block ticking ring. Chunks are counted from the chunk the spawn point is in, so a spawn near a chunk border moves the whole square: check the ranges above rather than counting from the spawn block.