What is the BBMODEL file format?
A .bbmodel file is the native project format of Blockbench, a free 3D model editor made by the developer JannisX11 and first released in 2017. Blockbench is used mostly for low-poly models with pixel-art textures, and it is the common tool for building custom models for Minecraft. Mojang Studios supports its development, and the source code is open under the GPL-3.0 license.
The file is JSON text, so it is human-readable, but it is not a general interchange format. It holds the full project state: geometry elements such as cubes and meshes, the group and outliner hierarchy that defines the bone structure, texture references or embedded images, animations, animation controllers, and display transforms. Textures can be embedded directly as Base64 data:image/png;base64 URLs or linked by file path. Each file records a meta.format_version, which has reached 5.0, with breaking changes at 4.9, 4.10 and 5.0. Some projects are LZUTF8-compressed and start with a literal <lz> marker instead of a JSON brace.
Security & safety
RISK: LOWA .bbmodel is JSON text describing geometry and textures, not executable code, so opening one does not run anything. The main caution is that embedded Base64 textures can make files large, and hand-editing the JSON can corrupt the project. Only open files from sources you trust and keep Blockbench updated.
Format details
in a nutshellPrograms that open BBMODEL files
Windows2 apps
Blockbench (Desktop)
Open-source Install the desktop app, then choose File > Open to load and edit the .bbmodel project with full 3D preview, texturing and animation. 
Visual Studio Code
Free Open the .bbmodel file as text to inspect or hand-edit the raw JSON structure (works only for uncompressed files). 
macOS2 apps
Blockbench (Desktop)
Open-source Launch Blockbench and open the .bbmodel project to view and edit geometry, textures and animations. 
Linux2 apps
Blockbench (Desktop)
Open-source Run the AppImage or installed build and open the .bbmodel project for editing.
gedit / any text editor
Open-source Open an uncompressed .bbmodel to read or edit its JSON directly.
Blockbench Web App
Open-source Open web.blockbench.net in a browser and load the .bbmodel with no installation needed. Technical details
deep spec| Encoding | UTF-8 JSON text; optionally LZUTF8-compressed with a leading <lz> ASCII marker |
| Byte order | N/A (text) |
| Container | Single JSON object |
| Compression | Optional LZUTF8 (Blockbench setting). Compressed payloads are prefixed with the literal string <lz> |
| Typical size | A few KB to several MB, depending on embedded Base64 textures and animation data |
| Structure | Top-level JSON object with meta (format_version, model_format, box_uv, backup flags), resolution (texture width/height), elements (cubes, meshes, locators with positions, rotations and UV data), groups and outliner (bone hierarchy / scene tree), textures (metadata plus optional embedded data URLs or file paths), animations, animation_controllers, display (item/block display transforms), and optionally editor_state and history (undo stack). |
| Platforms | Windows, macOS, Linux, Web |
| Notes | There is no complete published specification of the JSON schema. The format carries a version field and has had breaking changes at versions 4.9, 4.10 and 5.0. Blockbench itself recommends a custom plugin format rather than parsing bbmodel directly for external loaders. Textures may be stored embedded as data:image/png;base64 URLs or referenced by absolute/relative path. |
| Model Format | The meta.model_format field records the project type: Java Block/Item, Bedrock Entity, Generic (Free), Skin, and others |
| Released | 2017 (Blockbench 1.0, May 5 2017) |
| Latest version | Format version 5.0 |
| Specification | www.blockbench.net |
BBMODEL conversions
Community Q&A
asked by usersNo questions yet - be the first to ask about BBMODEL files.
