Convert FBX to GLB Online
Convert Autodesk FBX (Filmbox) files to GL Transmission Format Binary (GLB), entirely in your browser. No upload, no sign-up. Your files never leave your device.
Drop your FBX file here
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Medieval lantern with dark iron, bronze accents, and warm glass — multi-material FBX model for format conversion testing.
FBX files often carry skeletal rigs, keyframe animations, and blend shapes. The conversion retains this motion data in GLB's standardized animation format.
FBX is a proprietary Autodesk format. GLB is built on glTF, an open Khronos Group standard published as ISO/IEC 12113, ensuring broad tool and platform support.
FBX targets desktop content-creation tools. GLB is optimized for fast delivery and real-time rendering in browsers, AR platforms, and game engines.
Also convert from FBX
Other ways to get GLB
How to Convert FBX to GLB
Animations, rigs, and materials carried over; just drop your .fbx file.
Upload FBX
Drag and drop or select your .fbx file. FBX bundles geometry, materials, skeletal rigs, and animations into a single file.
Processing
Conversion runs entirely in your browser. Meshes, PBR materials, skeletal rigs, and keyframe animations are extracted from the FBX and repacked into the open GLB format.
Download GLB
Get your ready to use GLB file with animations and materials preserved. The result loads natively in web browsers, AR platforms, and game engines; no proprietary SDK needed.
Why convert FBX to GLB?
FBX is a proprietary file format originally developed by Kaydara and now owned by Autodesk. It is a staple in professional 3D workflows across film, games, and animation because it stores meshes, materials, skeletal rigs, and animation data in a single file. However, its proprietary nature means that broad interoperability depends on Autodesk's SDK, and web browsers and AR platforms have limited or no native FBX support.
Converting to GLB removes that dependency. GLB is the binary form of glTF, an open standard maintained by the Khronos Group and ratified as an international standard (ISO/IEC 12113). It packages geometry, PBR materials, textures, and animations into a single compact binary built for real-time rendering. The result is an asset that loads natively in web viewers, AR experiences, and engines like Unity and Unreal, with no proprietary tooling required.
Key advantages of GLB over FBX
GLB is based on glTF, an open Khronos Group standard ratified as ISO/IEC 12113.
GLB loads natively in browsers via WebGL and WebGPU without plugins or proprietary SDKs.
GLB's binary packing and optional Draco compression produce significantly smaller files than FBX.
GLB uses a standardized physically based material model ensuring consistent appearance across renderers.
GLB is the required 3D format for AR experiences on Android and WebXR. iOS AR Quick Look uses USDZ.
GLB does not depend on any single vendor's SDK for reading or writing.
FBX vs GLB
| Feature | FBX | GLB |
|---|---|---|
| File structure | Binary or ASCII (single file) | Single binary container |
| Animation | Full skeletal, morph, keyframe | Full skeletal, morph, keyframe |
| Materials | Phong/Lambert (PBR inconsistent) | PBR metallic-roughness (standardized) |
| Textures | Embedded or external (JPEG, PNG, TGA) | Embedded (JPEG, PNG, KTX2) |
| Compression | Deflate on arrays only | Draco, meshopt, KTX2 |
| Specification | Proprietary (Autodesk) | Open standard (Khronos) |
| Web support | Poor (reverse-engineered loaders) | Excellent (native web format) |
When to Use Each Format
Use FBX when
- Working inside the Autodesk ecosystem (Maya, 3ds Max, MotionBuilder)
- Importing animated assets into Unity or Unreal Engine
- Your studio's pipeline is built around FBX as the interchange format
- You need animation stacks with multiple named clips in one file
Use GLB when
- Publishing 3D content on the web or in AR experiences
- You want standardized PBR materials that render consistently everywhere
- File size must be minimized with Draco or meshopt compression
- You want an open, vendor-neutral format with long-term viability
Known Limitations
FBX's Phong/Lambert materials are converted to PBR metallic-roughness, which requires heuristic mapping and may look different
Unit conversion from centimeters (FBX default) to meters (glTF default) can introduce scale issues if not handled
FBX animation layers with blend modes are flattened into simple keyframe tracks
TGA and BMP textures are re-encoded to PNG or JPEG since glTF does not support those image formats
FBX to GLB FAQ
Are FBX animations preserved in the GLB output?
Yes. Skeletal animations, morph targets, and transform keyframes all transfer to GLB. Both formats have strong animation support, so this part of the conversion is reliable.
Why do my materials look different in GLB?
FBX uses Phong or Lambert shading, while GLB uses PBR metallic-roughness. The converter estimates PBR values from the Phong properties, but the visual result under realistic lighting may differ. Manual tweaking of roughness and metallic values can help.
Is converting FBX to GLB a good idea for web use?
It's one of the most common conversion paths. GLB is the standard format for web 3D (three.js, Babylon.js, model-viewer). Converting from FBX to GLB lets you bring game-engine or DCC assets to the web with good compression and broad browser support.
Will the file be smaller as GLB?
Almost always, especially with Draco compression enabled. FBX uses basic deflate on internal arrays, while GLB supports specialized geometry and texture compression that can reduce file size dramatically.
Why Studios Are Leaving FBX Behind
FBX has been the default interchange format in 3D production for over a decade. Maya, 3ds Max, and MotionBuilder all export it natively. Game engines ingest it without complaint. But FBX carries a fundamental constraint: it is a closed, proprietary format owned by Autodesk. The specification is not public. Third party tools that read or write FBX must either license the Autodesk FBX SDK (which prohibits redistribution and is incompatible with open source licenses like the GPL) or rely on reverse engineered parsers that handle only a subset of the format's features.
GLB solves this. It is the binary packaging of glTF 2.0, an open standard maintained by the Khronos Group and ratified as ISO/IEC 12113. Any developer can read the specification, build a loader, and ship it without legal restrictions. Web browsers, AR platforms, and engines like Unity, Unreal, and Godot all support glTF natively. For studios delivering 3D content to the web, to product configurators, or to AR experiences, GLB is the target format. The question is how to get there from a library of FBX files without losing what matters.
Coordinate Systems and Unit Conversion
FBX and glTF disagree on which direction is up. FBX files can be either Y-up or Z-up depending on the authoring tool. Maya exports Y-up by default. 3ds Max exports Z-up. The FBX file header contains a flag indicating the coordinate system, but not every exporter sets it correctly.
glTF is always Y-up, with +Z pointing toward the viewer and +X pointing right. A converter must read the FBX coordinate flag, apply the appropriate rotation to the root node, and ensure all transform hierarchies remain consistent. When this step fails, models appear sideways or upside down in the web viewer.
Units also differ. FBX defaults to centimeters. glTF uses meters. A model that is 180 units tall in FBX should become 1.8 meters in GLB. The converter applies a uniform scale factor during the root transform. If your FBX files were authored with a nonstandard unit scale (some game studios use 1 unit = 1 inch), you may need to set the correct scale factor before conversion.
Translating Materials from Phong to PBR
This is where most visual differences appear. FBX stores materials using older shading models: Lambert (diffuse only, no specular) and Phong (diffuse plus specular highlight controlled by a shininess value). Some FBX files from Maya use the Stingray PBS material, which is closer to PBR, but this is uncommon in legacy assets.
glTF uses a single material model: PBR metallic-roughness. Every surface is described by a base color, a metallic factor (0.0 for dielectric, 1.0 for metal), a roughness factor (0.0 for mirror smooth, 1.0 for fully rough), and optional normal, occlusion, and emissive maps.
The converter maps between these systems using heuristics. Diffuse color becomes base color. Shininess is inverted to produce roughness (high shininess yields low roughness). Specular intensity informs the metallic estimate. The results are reasonable for matte and semi-glossy surfaces. Highly reflective metals and complex specular setups often need manual adjustment after conversion, because the energy conservation rules in PBR differ from the additive specular model in Phong.
Texture maps also change roles. A diffuse texture becomes a base color texture. Specular and glossiness maps get reinterpreted or discarded. Normal maps transfer directly. If the FBX contains TGA or BMP textures, these are re-encoded to PNG or JPEG since glTF only supports JPEG, PNG, and WebP image formats.
Animation Baking and Layer Flattening
FBX has a powerful animation system. It supports multiple animation stacks (named clips), animation layers with blend modes (additive, override), and curve-based interpolation with custom tangent handles. glTF supports animation too, but with a simpler model: named animations containing channels that target node transforms (translation, rotation, scale) or morph target weights, with linear, step, or cubic spline interpolation.
The conversion process bakes FBX animations into glTF. Baking means stepping through the animation frame by frame at a fixed sample rate (typically 24, 30, or 60 frames per second), evaluating the full animation stack including all layers and blend modes, and recording the resulting transform for each bone at each frame. This produces dense keyframe data that faithfully reproduces the motion but loses the original curve structure.
For most use cases this is fine. Web viewers play back the baked animation identically to the original. The tradeoff is file size: baked animations with many bones sampled at 60 fps produce large buffers. If your animations are long, consider baking at 30 fps or 24 fps. The visual difference is often negligible for character animation, and the file size drops proportionally.
Morph targets (blend shapes) transfer cleanly. Both formats store them as vertex position deltas. Named morph targets keep their names, which matters if your web viewer drives facial expressions by name.
Validating the Output Before Shipping
After converting an FBX file to GLB, run through these checks before deploying the asset:
- Orientation. Load the GLB in a web viewer (three.js editor, model-viewer, or the Babylon.js sandbox). Confirm the model is upright and facing the expected direction. If not, the coordinate system conversion needs adjustment.
- Scale. Verify that the model dimensions match expectations. A human character should be roughly 1.7 to 1.8 meters tall, not 170 or 0.017. Check the bounding box in your viewer.
- Materials. Compare the GLB side by side with the original FBX in your DCC tool. Pay attention to metallic surfaces, glass, and anything with strong specular highlights. These are the areas most likely to shift during the Phong to PBR translation.
- Animation playback. Play every animation clip. Check that bones do not pop, twist incorrectly, or drift over time. Verify that morph targets activate and deactivate smoothly.
- File size. Compare the GLB size against the original FBX. If the GLB is larger, the baked animation data may be inflating it. Consider reducing the bake framerate or enabling Draco geometry compression, which can cut geometry buffer sizes by 80 to 90 percent.
- Texture quality. Confirm that textures are sharp and correctly mapped. Look for UV seams, flipped normals, or missing textures that might indicate a failed texture re-encoding step.