Convert OBJ to GLB
Free OBJ to GLB converter that runs in your browser. See real dimensions before you download.
Why convert OBJ to GLB?
OBJ to GLB is the usual route from a classic modelling export to something you can use on the web or in AR. An OBJ arrives as several files (the mesh, an MTL and loose texture images) that are easy to break apart. GLB bundles all of it into one file that Three.js, Babylon, model-viewer, Shopify-style 3D previews and AR tools load directly. Geometry, UVs, normals and texture images are carried over, and colours from the MTL become glTF materials. OBJ has no unit, so the scale you assume matters: GLB uses metres, and an OBJ authored in millimetres would look 1000 times too large unless you scale it. MeshShift shows the real dimensions first so you can pick the right factor.
How to convert OBJ to GLB
- Drop your OBJ file (with its textures, if separate) onto the converter — it opens in your browser, nothing is uploaded.
- Check the preview and the dimensions in mm; fix units or the up axis in “Units & orientation” if the size or orientation looks wrong.
- Choose GLB as the output and click Convert. Several files download as one ZIP.
What carries over from OBJ to GLB
| OBJ | GLB | Result | |
|---|---|---|---|
| Colour / materials | Yes | Yes | Kept |
| Textures | Yes | Yes | Kept |
| Units stored in file | No | Yes | Written as mm → metres |
| Separate parts | Yes | Yes | Kept |
| Usual up axis | Y | Y | Unchanged |
What changes
- Several files (OBJ, MTL, images) become one self-contained GLB.
- MTL colours and texture maps become glTF materials; older Phong settings are approximated.
- Units are reinterpreted as metres in GLB, so scale is chosen during conversion.
- Object names are kept where possible, but OBJ's groups are simpler than glTF's node tree.
Tips
- Upload the OBJ with its MTL and texture images, so materials and textures are found.
- Check the dimensions in the viewer: a model meant to be 50 mm should show 0.05 m in GLB terms.
- Compress large textures first if the GLB will be loaded on a web page.
- Triangulated meshes load fastest; OBJ quads are split during conversion.
About OBJ files
OBJ comes from Wavefront Technologies' Advanced Visualizer software in the 1980s, and it has outlived the product. A file is plain text: lines starting with v define vertices, vt texture coordinates, vn normals, and f faces that reference those lists by index. Faces may be triangles, quads or larger polygons, and the g and o keywords group faces into named objects. Appearance is not in the OBJ at all; a line called mtllib points to a separate .mtl file that lists materials with diffuse colours and texture image names. The format is verbose, has no official unit and no scene hierarchy or animation, but it is trivial to read and write. That is why scanners, photogrammetry tools, sculpting programs and game pipelines still use it to move static meshes around.
About GLB files
GLB is the binary container for glTF 2.0, the format the Khronos Group describes as the JPEG of 3D. One .glb file bundles a JSON scene description, binary mesh buffers and embedded images, so nothing can go missing in transit. The format was designed for efficient delivery and loading on the web, and it is now used by Three.js, Babylon.js, model-viewer, Google Search 3D results, Meta platforms, Unity and Unreal importers, and many marketplaces such as Sketchfab. glTF defines a physically based metallic-roughness material model, a node hierarchy, cameras, skins and animations. Coordinates are in metres with +Y up and a right-handed system. It is excellent for display and game assets, but it is a presentation format rather than a manufacturing one, so print workflows usually convert it first.
3D printing notes
Slicers import OBJ geometry and ignore the material file, so what you print is the shape only. Bambu Studio and OrcaSlicer can use the colours from an OBJ for multi-colour assignment on import, but results depend on the exporter. The main trap is orientation and scale. Blender usually writes Y-up files while slicers expect Z-up, so a model may arrive lying on its back, and a model sculpted at one unit per metre can be tiny. MeshShift has an Up-axis fix that rotates Y-up models so they stand upright, shows real dimensions before conversion, and can convert OBJ to STL or 3MF in the browser.
Frequently asked questions
Do I need to upload the MTL and textures too?
Yes, include them if you want the colours and textures in the GLB. Without them the converter only has the shape and will produce an untextured model.
Why does my model look huge in the AR viewer?
OBJ has no unit, while GLB is in metres. If the OBJ was modelled in millimetres or centimetres, apply the matching scale during conversion so the real-world size is right.
Is this OBJ to GLB converter free and private?
Yes. The conversion runs in your browser with JavaScript and WebAssembly, so your OBJ file is never uploaded to a server. There is no sign-up, no watermark and no daily limit; very large files are limited only by your device's memory.