Chunk coordinate calculator.

Find chunk boundaries, local block positions and Java region files.

Block XBlock Z

Result

Chunk X 0, Z -1
Position inside chunk: X 0, Z 15
X boundary: 0 to 15
Z boundary: -16 to -1
Java region file: r.0.-1.mca

Negative coordinates work too

A chunk spans 16 blocks on X and Z. Coordinates are rounded down to the containing block, then divided with floor rounding. Block -1 belongs to chunk -1, not chunk 0.

Region files are Java-specific

Java Anvil regions contain 32 by 32 chunks. The region filename shown is a location guide, not a file editor. Back up a world before editing its files.

Free to use. No account required. Inputs stay in your browser.