GLB to FBX converter — rig and shape keys kept
VTubeMe's GLB to FBX converter turns your .glb into a binary FBX for Unity, Unreal and Maya, keeping the skeleton, skin weights and shape keys. Animation does not travel. Free, five conversions a day.
How do I convert a GLB to FBX?
Drop the .glb on this page and download the .fbx it gives back — three steps, nothing to install, and the rig comes with it.
- 1Drop your .glb into the box above, or click it and choose the file; sign in when prompted, there is nothing to pay. Rigged characters and static props both go through the same path, and the upload limit is 100 MB.
- 2Wait while it converts: the file opens in Blender on our server and is written back out as a binary FBX. The skeleton, the skin weights and the shape keys are written into the FBX rather than rebuilt; the rest pose is rebuilt so that bind equals rest, no leaf bones are appended, and the metre-to-centimetre unit change is baked into the vertices instead of being left as a ×100 scale.
- 3Download the .fbx and import it into Unity, Unreal, Maya, 3ds Max or Blender. Whether the textures come inside the file depends on the material graph, not on FBX: two of the four GLBs we tested produced no embedded images at all, so open the result in a viewer before you build on it.
- Accepts:
- one .glb, the binary form of glTF, up to 100 MB. A .gltf with its .bin and texture folder beside it is not a single file and is not accepted — re-export it as a .glb first.
- Returns:
- one binary FBX, version 7.4 — the flavour Unity, Unreal, Maya, 3ds Max and Blender all read. Never ASCII FBX.
- Costs:
- nothing, and no credits — an account, though: five conversions per account per rolling 24 hours, shared across all six free pairs. Conversions that fail are not counted.
- Measured:
- on one VRoid-exported GLB the result re-imported with the same 107 bones, three skinned meshes, 56 shape keys, 19 materials and 32,047 triangles.
- Animation does not travel: the skeleton is written and the motion curves are not, so the rig arrives in its bind pose.
- Textures depend on the material graph rather than on FBX: of four corpus GLBs we converted, two came back with their images embedded — one of them with six of its eight materials textured — and two came back with none, a VRoid Studio export among them, because its materials leave base colour unlinked.
- Materials are translated, not preserved: glTF extensions such as MToon toon shading or unlit have no FBX equivalent and come out as plain surfaces.
What actually happens to the file
The converter opens your .glb in Blender on our server and writes a binary FBX — the skeleton, the skin weights and the shape keys come with it, so the result is the same character in the container Unity, Unreal and Maya actually accept. It is free, with no account balance to top up.
A GLB is glTF's binary form: geometry, materials and textures in one file, plus an optional skeleton. FBX is Autodesk's interchange format and holds the same set of things under different names. So this is a re-container, not a rebuild — no decimation, no re-topology, no compression pass.
On one VRoid-exported GLB from our regression corpus the FBX came back with the same 107 bones, the same three skinned meshes, the same 56 shape keys, the same 19 materials and the same 32,047 triangles. That is the shape of a good conversion: the numbers on both sides match.
Two settings are worth knowing because their absence is what usually goes wrong elsewhere. No leaf bones are appended — Unity and Unreal read an appended “_end” joint as a real bone and the imported skeleton then stops matching the original. And the metre-to-centimetre unit change is baked into the vertex data rather than left as a ×100 scale on every node, which is the form that makes a viewer report a model 88 metres tall.
Why the rest pose is rebuilt on the way out
Some glTF exporters store vertices in a pre-skin space that only the inverse bind matrices map back to a human shape. Blender reads that correctly and its own round-trip agrees with itself, so the file looks fine until it reaches anything else: three.js-based viewers draw a needle-shaped soup instead of a character. We hit it on a real file — a converted cat left as an 88-metre diagonal line.
The conversion therefore evaluates each skinned mesh into its rest shape and rebuilds the armature binding so that bind equals rest, which is the convention every consumer agrees on. Shape keys are evaluated through the same step so they stay consistent with the new base.
What this conversion cannot do
Measured on real files, not assumed. Everything below is a property of the formats or of the pipeline, and knowing it beforehand is cheaper than discovering it in your 3D tool.
Animation does not travel
The skeleton is written, the motion curves are not. Reading an FBX's animation costs about 1.5 GB of memory on a long clip, which is more than the converter container has, so the importer is asked to skip it and the exporter writes none. A file that arrives with a walk cycle leaves with the same rig in its bind pose. If what you have is the motion rather than the model, the FBX to VRMA converter is the tool that keeps it.
Textures ride inside the FBX — unless the material hides them
Textures packed into the GLB are written into the .fbx itself, so one file carries everything. That works when the material binds an image to its base colour, and not every material does: of four corpus GLBs we converted, two arrived with their images embedded — one of them with six of its eight materials textured — and two arrived with none, among them a VRoid Studio export whose materials are wired through a mix shader with nothing on base colour. It is not an FBX limitation; the same file converted to OBJ loses its textures in the same way. Open the result in the free FBX viewer before you build on it; if it is grey, the images are still inside your GLB and can be re-linked by hand in your 3D tool.
Materials are translated, not preserved
glTF describes a material with metallic-roughness PBR; FBX has its own, older material model. The base colour, the maps and the obvious factors carry over, and anything expressed as a glTF extension — unlit, MToon toon shading, transmission, clearcoat — has no FBX equivalent and comes out as a plain surface. Every GLB-to-FBX converter has this limit; re-pick the shading in your target app.
Five conversions a day, per account
This pair is free and takes no credits, but one account gets five conversions per rolling 24 hours across all six pairs together — the converter is one machine and this is what keeps it answering. Each slot frees itself 24 hours after it was used; nothing expires at midnight. Conversions that fail are not counted.
Frequently asked questions
Does the rig survive a GLB to FBX conversion?
Yes — the skeleton, the bone hierarchy and the per-vertex skin weights are all part of both formats, so they are carried across rather than rebuilt. On a VRoid-exported GLB we measured 107 bones in and 107 bones out, with all three skinned meshes still bound. What does not survive is animation: the motion curves are skipped on purpose, so the rig arrives in its bind pose.
Will my blendshapes / morph targets still be there?
Yes. glTF morph targets become FBX blend shapes; on the same test file all 56 came through. The exporter is told not to apply modifiers, because applying them is what silently destroys every shape key in an FBX export — a well-known trap when people do this by hand in Blender.
Is this the same as converting a GLB to VRM?
No, and it is worth being clear about it: FBX is an interchange format for 3D software, while VRM is an avatar format that VTubing and social-VR apps load directly. If your GLB is a rigged character and the destination is VSeeFace, Warudo, VNyan or VRChat, converting to FBX just adds a step — go straight to VRM instead. GLB to VRM converter →
Can I convert a .gltf file instead of a .glb?
Not on this page. A .gltf is only the text half of a model — the geometry sits in a .bin beside it and the textures in a folder beside that — so a single .gltf upload arrives incomplete. Open it in the free glTF viewer by dropping the whole folder if you only want to look at it, or re-export it as a single .glb from your 3D tool and convert that. Open the GLB / glTF viewer →
Binary or ASCII FBX?
Binary, version 7.4 — the flavour Unity, Unreal, Maya, 3ds Max and Blender all read. ASCII FBX is the text dialect that most importers, ours included, refuse; you will never get one from here.
Do you keep my file?
The conversion runs Blender on our server, so the file is uploaded — it is not a browser-side tool and we do not pretend otherwise. The upload and its result live on disk long enough for you to download them and are removed afterwards. If you only want to look at a model, the viewers do run entirely on your own device and nothing leaves it.
The other format pairs
All six are free, all six run the same pipeline, and all six say what they drop.
GLB to OBJ
GLB in, OBJ out — free, zipped with its materials.
FBX to GLB
FBX in, GLB out — free, one file.
FBX to OBJ
FBX in, OBJ out — free, zipped with its materials.
Blender (.blend) to FBX
Blender (.blend) in, FBX out — free, one file.
OBJ to GLB
OBJ in, GLB out — free, one file.
Only want to look at the file? GLB viewer, FBX viewer and OBJ viewer all run on your own device — nothing is uploaded.
Is your model going into VTubing?
If the GLB you just converted is a rigged character and it is going into VTubing or social VR, FBX is a detour. The same file becomes a VRM — humanoid bones mapped, materials converted to MToon — that VSeeFace, Warudo and VNyan open directly.
Open the VRM converter