Free GLTF to GLB Converter
Lightning-fast GLTF to GLB conversion — 100% in your browser. Your files never leave your device. Free, no watermark, no sign-up.
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Supports GLB, GLTF, OBJ, STL, FBX, PLY
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GLTF vs GLB
See what transfers when converting between these two formats.
| Feature | GLTF | GLB |
|---|---|---|
| Geometry | ||
| Textures | ||
| Materials | ||
| Animation | ||
| Rigging |
All features supported by GLTF are preserved in GLB.
Why convert GLTF to GLB?
Ship 3D models to the web
Three.js, model-viewer, Babylon.js, and PlayCanvas all load GLB natively. A single .glb file avoids the multi-request overhead of .gltf + .bin + textures.
AR and WebXR experiences
Apple Quick Look, Google Scene Viewer, and WebXR sessions all expect GLB. GLTF with external files is unreliable in these contexts.
Bundle assets for delivery
Distribute one file per model instead of a folder with 10+ assets. Simpler for CDN, simpler for users, simpler for app bundles.
Tips for GLTF → GLB
Resolve all external references first
If your GLTF references textures or buffers that are missing, the conversion will produce a broken GLB. Make sure every URI in the .gltf file resolves.
Compress textures before bundling
GLB inlines textures, so a 4096×4096 PNG becomes 24MB inside the .glb. Resize or use KTX2 compression before converting for faster web loads.
Use Draco or Meshopt for smaller files
Fast3D writes uncompressed GLB by default. For production web delivery, run the file through gltfpack or glTF-Transform to apply mesh compression.
Test in model-viewer
converterPages.deepContent.pair.gltf-to-glb.tips.items.3.desc
Common issues when converting GLTF to GLB
Conversion fails with 'buffer not found'
Fix
The .gltf file references a .bin file that is not in the same folder. Move the .bin next to the .gltf and try again. Check the `buffers` array in the .gltf JSON for the exact filename expected.
GLB loads but textures are black
Fix
The GLTF referenced external texture images by URI but they were not bundled. Re-convert with all image files present in the source folder.
GLB is much larger than the GLTF source
Fix
GLB inlines everything, so the total size equals the sum of all source files. Compress textures (KTX2, WebP) or apply Draco mesh compression to shrink the output.