FBX to GLB

FBX to GLB, without installing Blender

FBX is the format game engines and DCC tools trade in. Unity, Unreal, Maya, 3ds Max, Mixamo and most asset stores hand you FBX. The web doesn't speak it. three.js, Babylon.js, <model-viewer>, Android's Scene Viewer and most online 3D embeds want glTF, and GLB is glTF packed into one binary file. Converting FBX to GLB is the usual step between a game asset and a web page.

The converter reads the FBX in your browser, shows it in a 3D preview, and writes a GLB with the meshes, materials, textures and animations inside. Nothing is uploaded. The file is read and written on your own machine.

What carries over into the GLB

GLB is one of the few formats that can hold almost everything an FBX character or prop has. The gaps are mostly in how materials are described.

Meshes and hierarchy

Kept. Each FBX mesh becomes a glTF mesh, with its node transforms.

Skeletal animation

Kept. Every clip in the FBX is written to the GLB. The converter's info panel counts them; to play them first, open the file in the FBX Viewer.

Morph targets (blend shapes)

Kept, along with their animation.

Embedded textures

Kept and packed into the GLB.

External textures

Kept if you drop the image files together with the .fbx. Otherwise the material keeps its color but loses the image.

Materials

Converted to glTF's metallic-roughness PBR. FBX Phong and Lambert materials have no exact PBR equivalent, so shininess and specular values are approximated. Expect the look to shift a little.

Cameras, lights, custom properties

Not part of the output. glTF is about the model itself.

How to convert FBX to GLB

1. Drop the .fbx onto the converter. If the textures sit next to it as separate files (a common setup for asset store downloads, often in a 'textures' folder), select them too and drop everything at once.

2. Check the preview. Orbit around, look at the textures, and check the animation count in the info panel. If something is gray or missing here, it will be missing in the GLB as well, so this is the moment to add the missing images.

3. Click Convert. The .glb downloads straight away, and its size is shown afterwards.

FBX and glTF both treat Y as up, so there's no up-axis switch for this pair. FBX files saved Z-up (some 3ds Max exports) are turned upright when they are read, so they come out standing in the GLB.

"FBX version not supported" and other problems

Most FBX trouble comes from the age of the file or from units, not from the conversion itself.

To check an FBX before converting it, open it in the FBX Viewer.

FBX version not supported

The file is FBX 6.x or older. Only FBX 7.0 and newer are read. Run it through Autodesk's free FBX Converter to save it as a current version, or re-export it from the app that made it. Blender's importer reads only FBX 7.1 and newer, so it cannot open the old file either.

Model is 100 times too big

Many FBX files are in centimeters; glTF viewers assume meters. The converter keeps the numbers as they are, so a 180 cm character arrives 180 units tall. Fix the scale in the source app (Unity's FBX scale factor, Blender's export scale) or scale it down in the target scene.

Textures are gray or pink

The textures were external and weren't dropped with the .fbx, or the FBX points at absolute paths from someone else's computer. Drop the image files alongside the model; they are matched by file name.

Character looks shiny or plastic

That's the Phong-to-PBR approximation. Adjust metalness and roughness in the target engine, or re-author the materials as PBR in Blender before exporting.

Animation missing or broken

The rig probably relies on constraints, IK or deformers that only the source app evaluates. Bake the animation to the bones in Maya, Max or Blender and export the FBX again.

Using the GLB afterwards

In three.js, load it with GLTFLoader; in Babylon.js, with SceneLoader. For a product page, <model-viewer src="model.glb"> is the shortest route. If you also need the model to open in AR on an iPhone, convert the GLB on to USDZ, since iOS Quick Look doesn't open GLB.

GLB from FBX tends to be large, because textures are often 4K PNGs. The conversion re-encodes textures but only scales down those larger than 4096 px, so 4K maps keep their size. If the file is too heavy for the web, shrink the textures before converting or run the GLB through a glTF optimizer afterwards.

For a mesh-only export with no rig or textures, use FBX to OBJ instead.