Bedrock NBT Editor vs MCA JSON

Bedrock NBT Editor is a free browser-based tool for editing Minecraft Bedrock Edition and Java Edition NBT files. It accepts files such as level.dat, playerdata, .nbt, .mcstructure, .schem, and .schematic, and detects byte order, headers, and compression across five NBT encodings. Users can search tags, add or remove them, change values, and download the edited file. The editor can also export the tree as SNBT text and convert between Bedrock files and Java big-endian gzip format. For large files, typed arrays and lazy rendering display 200 entries at a time; BigInt preserves 64-bit TAG_Long values such as world seeds and UUID halves. Files are parsed locally, with no upload endpoint, and the editor continues to work offline after the page loads. Android users can choose a world file from a file manager; iOS users must first put it in the Files app. The project is open source under the MIT license. The maker says it is not affiliated with Mojang Studios or Microsoft.

MCA JSON is a command-line toolkit and TypeScript library for handling Minecraft Java Edition region and data files. Its commands convert MCA and NBT data to JSON and back, list chunks, find signs, remove chunks, and inspect player locations. The library supplies typed methods for parsing and changing MCA, NBT, and SNBT data. The maker reports region structure and NBT reading across versions, with files tried from Minecraft 1.2.1 through 1.21. It reads zlib, gzip, LZ4, and uncompressed chunks; changes are saved with zlib. Installation is documented through npm, with Deno, Bun, pnpm, and other package managers also usable. The library can be bundled for browser use, is distributed only as ES modules, and requires Node.js 20 or newer. It supports Java Edition, not Bedrock. Separate .mcc chunks over 1 MiB and chunks using custom compression cannot be read, though they can be listed and removed. A largely untouched region produced about 1 gigabyte of JSON in an example; compact and condensed output options are documented. The software is free.