Origin
glTF was designed as a runtime 3D asset format: a way to move 3D scenes into web and app engines without heavy conversion at load time. Khronos positions it as a transmission format for 3D, much like JPEG is a transmission format for photos.
GLB is the binary form of glTF. Instead of a JSON file plus separate buffers and textures, a GLB can package everything into one portable file.
Technical characteristics
glTF can describe nodes, meshes, cameras, animations, skins, physically based materials, textures, and binary buffers. That makes it far richer than STL. It can carry how a model should look, not only what triangles form its surface.
The format is still a delivery format, not a full authoring-project format. It is excellent for exporting from 3D tools into viewers, websites, AR previews, and game engines, but original modeling files may contain construction history and editor data that glTF does not preserve.
Where it fits
Use GLB/glTF for web 3D viewers, AR previews, product models, game-ready assets, and image-to-heightmap experiments that should open in modern 3D software with materials. Use STL when a slicer only needs a surface for printing.
A practical rule: if you want a 3D asset to look right in a viewer, choose GLB. If you only need a printable shape, STL may be enough.
Best uses
- Web and app 3D delivery
- Models with materials or textures
- Portable previews and AR-style workflows
Use another format when
- Legacy slicers that only accept STL
- Full CAD construction history
- Long-term storage without source modeling files