Online NBT Editor
Open a .nbt, .dat or .schematic file and edit the tag tree directly — change a value, type, key, add or remove entries — with full undo/redo. Automatically detects Java (gzip) and Bedrock (little-endian), search by key or value, and compare two trees side by side. For Java .mca and .mcr regions, pick a chunk in the 32×32 grid, edit its tags and download the modified region as a new file.
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How it works
The parser reads NBT tags and Modified UTF-8 strings. For Java region files, the editor lists chunks from the header and decompresses only the selected chunk. Edits are kept when switching chunks; export creates a new file, recompressing edited chunks with zlib and preserving the compressed data of untouched chunks. Corrupt regions or overlapping sectors cannot be exported. Close the game and make a backup before replacing files. Bedrock world LevelDB databases are not supported; standalone Bedrock NBT files are still accepted.
- Region .mca/.mcr files: chunk grid and list by size or date, chunk and block coordinates, on-demand reading
- Gzip, zlib, uncompressed and LZ4 chunks, with external .mcc attachments; export a .nbt chunk or edited region
- Automatic detection of variant (Java/Bedrock), compression and endianness, with a manual override when the guess is wrong
- Editable tree: change value, key, type, duplicate, remove, move and add a tag, with full undo/redo
- Search by key or value with navigation between results, like the browser Ctrl+F
- Diff against the original file or between two different files, tag by tag
- Export as binary .nbt (same variant as the source file) or as SNBT (text) to copy
Frequently asked questions
How do I edit my world's level.dat?
Open the level.dat file in your save folder, with the game closed. The tree shows the world rules, name, seed, time and spawn position. Change the value you want, download the edited file and replace the original — keeping a copy of the old one first.
Can I edit an inventory through playerdata?
Yes. Files under playerdata/ hold an Inventory list, one compound per item: id, Count and its components. Changing Count or swapping the id changes what the player has on joining. The world must be closed, or the game overwrites the file when it saves.
What is the difference between NBT and SNBT?
NBT is the binary format the game writes to disk. SNBT is the text form of the same data, similar to JSON, the one you see in commands like /give and /data. This tool reads the binary and exports both: .nbt to go back into the game, and SNBT to paste into a command.
Does it read world files (.mca)?
Yes, Java .mca and .mcr regions. Open the region, select a chunk in the grid or list, edit its NBT tree and download the chunk or edited region. External chunks need their matching c.<x>.<z>.mcc file. Bedrock world LevelDB databases are not supported.
Does it work with modded worlds?
Yes. Mods usually add their own tags, and because the editor reads the tree from the format spec rather than from a list of known fields, a mod tag shows up just like a vanilla one. Large mod save files open normally.
Is my save uploaded anywhere?
No. Parsing, editing and serialization all happen entirely in your browser. No byte of the file ever leaves your machine, and you can confirm it in the Network tab.
Will the edited file still work in-game?
The tool preserves the original file variant (Java or Bedrock), compression and tag order when saving, so the result should open normally. Still, back up your save before editing.