What is glTF?
glTF (GL Transmission Format) is an open, royalty-free standard from the Khronos Group for delivering 3D models and scenes efficiently to apps and browsers.
glTF is often described as "the JPEG of 3D". It's a delivery format designed to load fast and render the same way everywhere, rather than an editing format full of tool-specific data.
glTF vs GLB
| .gltf | .glb | |
|---|---|---|
| Structure | JSON plus separate .bin and image files (or embedded base64) | One binary file |
| Human-readable | Yes, the JSON part | No |
| Best for | Debugging and hand-editing | Shipping and sharing |
The two hold exactly the same data, and tools convert between them losslessly.
Extensions
The core spec is deliberately small. Extensions add features such as Draco and meshopt geometry compression, KTX2 and WebP textures, and extra material properties like transmission, clearcoat and sheen. Not every viewer supports every extension, so test the target app.
Written with AI assistance and reviewed by the Renderlyst team. Corrections welcome at alishbakhalid766@gmail.com.