model/gltf+json MIME Type

Learn what the model/gltf+json MIME type represents, how to open glTF JSON scenes, and how Poly supports them.

MIME type details for model/gltf+json

In active use
MIME typemodel/gltf+json
Extensions
.gltf
First standardized2017
Created byKhronos Group
Browser supportChrome, Edge, Firefox, Safari
Example applicationsBlender, Khronos glTF Sample Viewer
Poly supportYes. Poly recognizes glTF scenes and makes supported geometry and scene metadata available.
Indexed by PolyYes. Poly indexes filenames and creates visual similarity information for supported 3D content; available scene metadata is shown in details.
Preview in PolyYes. Poly previews supported glTF geometry and scene content.
Poly agentYes. An optimized rendition of the 3D object or scene is provided to the agent, allowing compact yet information-rich multimodal interaction with 3D files.

What does model/gltf+json represent?

model/gltf+json is the registered media type for glTF JSON, normally stored as .gltf. Its JSON scene references meshes, materials, buffers, images, nodes, skins, and animations. Buffers and images can be external or embedded as data URIs.1

Because resources can be separate, move a glTF file with every referenced buffer and image. Validate the JSON and resource paths before rendering. .glb packages the scene into Binary glTF when one delivery file is more convenient.

Opening and converting glTF JSON

Blender documents import and export for glTF 2.0.2 The Khronos glTF Sample Viewer provides a browser view for sample assets.3 Export to GLB when a single binary delivery file is easier to distribute. Use a dedicated 3D editor for rigging, material editing, and animation authoring.

Support in Poly

Poly previews supported geometry, makes the filename searchable, and provides visual similarity for supported 3D content. Available mesh, node, material, vertex, triangle, camera, light, and animation counts appear as metadata when present. An optimized rendition of the 3D object or scene is provided to the agent, allowing compact yet information-rich multimodal interaction with 3D files.

ConstructVerified handling
Meshes, nodes, and materialsSupported when valid glTF data is present
TexturesSupported when usable image resources are available
Cameras and lightsPoint, spot, and directional lights are supported; area-light behavior is approximate
Skins and animationSupported when represented; individual extension behavior can vary

Poly's view supports inspection and understanding. It does not replace an authoring application for editing, rigging, or exact export validation.

Format context and alternatives

Khronos designed glTF for efficient runtime delivery of 3D scenes. Its JSON form keeps the scene description and resource relationships visible.1 Choose GLB when one binary delivery file is more convenient. STL is useful for simple triangle surfaces, while 3MF targets additive manufacturing.

Footnotes

  1. Khronos Group. glTF 2.0 Specification. 2
  2. Blender Manual. glTF 2.0 importer and exporter.
  3. Khronos Group. glTF Sample Viewer.
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