Minecraft NBT Editor
Open any Minecraft NBT file — level.dat, playerdata, schematics — browse it as a tree, edit the values, and save a valid file back. Every field keeps its original NBT type.
Intended for your own single-player save files. Editing saves in multiplayer or online games breaks their terms of service and can get your account banned. Always keep a backup of the original file before you change anything.
Reads and writes Minecraft NBT for Java Edition (big-endian) and Bedrock (little-endian), handling gzip automatically. Edits are merged onto the original tag tree so every field keeps its exact type — a Byte stays a Byte and a 64-bit Long stays precise, which is what JSON alone cannot express. Values that will not fit their type are rejected with the exact path rather than silently truncated, and an unedited file rebuilds byte-for-byte identically.
How to use
- 1Drop level.dat, a playerdata file or any .nbt file.
- 2Browse the tag tree, or switch to the JSON view.
- 3Copy or download the whole structure as JSON.
Frequently Asked Questions
What is NBT?
Named Binary Tag, the format Minecraft uses for nearly all its structured data — world settings, player inventories, entities and schematics. It is a tree of typed, named tags, similar in spirit to JSON but binary and compact.
Where do I find these files?
level.dat sits in the root of each world folder, on Windows under %appdata%\.minecraft\saves\[world]. Player data lives in playerdata/[uuid].dat inside the same folder. Always copy a file out before opening it, and never edit a world that is currently loaded.
Does it work with Bedrock Edition?
Yes. Bedrock writes little-endian NBT and its level.dat has an 8-byte header before the root tag; both are detected automatically. Bedrock world data itself lives in a LevelDB database, which this tool does not read.
Why are some numbers shown as text?
64-bit Long values exceed what a JavaScript number can hold exactly, so they are rendered as strings to avoid silently corrupting them. World seeds are the usual case.
Can I edit and save the file?
Yes. Switch to the JSON view, change what you need, then click Apply edits and rebuild to download a valid NBT file. Editing works by merging your changes onto the original tag tree, so an unedited file rebuilds byte-for-byte identically.
How does it know whether a number is a Byte or an Int?
Because it does not have to guess. JSON cannot express NBT's types — the number 5 could be a Byte, Short, Int, Long, Float or Double — so instead of rebuilding from your JSON, the edits are applied onto the original tree and each field keeps the type it already had. Only brand-new keys need a type inferred, and every inference is listed for you to check.
What happens if I enter a value that does not fit?
It is rejected before anything is written, with the exact path and the allowed range — setting a Byte field to 999 tells you it must be between -128 and 127 rather than silently wrapping around and corrupting the save.
Will my world seed lose precision?
No. Seeds are 64-bit Longs, which JavaScript numbers cannot hold exactly, so they are shown and edited as quoted strings and written back as exact 64-bit values.
Should I back up before editing?
Always, and close the world first. Minecraft caches level.dat while a world is loaded and will overwrite your changes on exit. Edit only when the game is closed, and keep the original file until you have confirmed the world loads.