GLB to FBX: How to Convert (and What Gets Lost)

GLB is the binary container for glTF — the format Khronos Group designed to be the "JPEG of 3D". A single .glb file bundles mesh, materials, textures, animations, and skins into one self-contained asset, optimized for transmission over the network. It is the native format of WebGL, WebGPU, and AR viewers like Apple Quick Look and Android Scene Viewer.

• Single self-contained binary file (mesh + textures + animations)
• Native to web 3D, AR, and metaverse pipelines
• PBR material model (base color, metallic/roughness, normal, emission)
• Supports skinning, morph targets, and keyframe animation

FBX is the workhorse interchange format of the game and animation industries. Owned by Autodesk since 2006, its closed binary specification stores meshes, materials, textures, skeletons, animations, lights, cameras, and full scene hierarchies. Game engines (Unity, Unreal, Godot) and DCC tools (Maya, 3ds Max, Blender) all read and write FBX, even though no perfect open-source spec exists.

• Industry-standard for rigged characters and animations
• Closed binary format reverse-engineered by the FBX SDK and Blender
• Full scene graph: lights, cameras, hierarchy, constraints
• Not natively supported in browsers — convert to GLB for the web

GLB and FBX have overlapping capabilities, and most converters get the geometry right. The differences show up around materials, units, axis orientation, and what each tool downstream expects.

1. Blender (free, all platforms). Open Blender, File → Import → GLB (.glb), then File → Export → FBX (.fbx). Blender has native importers and exporters for every format on this page except STEP (which needs the optional CAD Sketcher addon or a separate STEP-to-mesh pass). The export dialog exposes the settings that matter: scale, axis orientation, and whether to embed materials and animations.
2. glTF-Transform CLI (free, scriptable). For glTF and GLB conversions, glTF-Transform is the most reliable command-line tool: install with npm, then run gltf-transform copy input.glb output.fbx. It also supports compression (Draco, Meshopt) and texture optimization, which matters if the converted file is going on the web.

Geometry-wise, GLB and FBX carry the same essential data, so this conversion is reasonably lossless.

• Importing into Unity or Unreal Engine for a game project
• Sending to an animator working in Maya or 3ds Max