3D File Converter: convert OBJ, FBX, STL and glTF online
Drop one or many 3D files, pick the output format and download the result. Units, up axis and origin are converted properly, textures are kept wherever the format allows it.
Your files never leave your device
Drop a file to see it here.
How to convert a 3D file
- Drop your files or click Choose files. For OBJ or glTF with textures, add all files together, drop the folder or a ZIP.
- Choose the output format. The options show what the format needs: unit and up axis for OBJ, STL and PLY, the 3D printing preset for STL.
- Check the preview and the info panel: size, triangles, materials, textures and warnings about missing files.
- Click Convert. The converter opens the result again to check it, then you download each file or all of them as one ZIP.
Input formats
GLB and glTF (with .bin and textures, also Draco, Meshopt and KTX2 compressed), FBX 7 and newer (binary and ASCII), OBJ with MTL and textures, STL (binary and ASCII), PLY, 3MF and Collada (DAE). ZIP archives and folders are unpacked in the browser.
What the converter does not do
- No FBX output: browsers cannot write clean FBX files. Every Grab3D library model has a ready FBX download.
- No BLEND, MAX or C4D files. Export them from the original program as FBX, GLB or OBJ first.
- No compression and no polygon reduction. Use the GLB Optimizer for that.
Output formats and what they keep
| Format | Keeps | Limits |
|---|---|---|
| GLB | Geometry, node hierarchy, PBR materials, embedded textures, skeleton, animations, morph targets. | No compression. WebP and KTX2 textures are stored as PNG. |
| glTF (ZIP) | Same as GLB, as .gltf, .bin and separate texture images. | Unpack the ZIP into one folder before you use it. |
| OBJ (ZIP) | Geometry, UVs, normals, vertex colors, one object per mesh, MTL with base color, roughness, metalness, normal and emissive maps. | No animation, no skeleton. Ambient occlusion is left out. |
| STL | Binary STL, all parts merged, with a watertight check. | Geometry only: no colors, UVs or materials. |
| PLY | Binary PLY with normals, UVs and vertex colors. Textures can be baked into vertex colors. | No materials or texture images. |
| USDZ | Geometry, PBR materials and textures for AR Quick Look on iPhone and iPad. | Static only, textures up to 2048 px, single sided. |
Popular conversions
Each page opens the converter with the right formats and explains what to watch out for.
Frequently asked questions
Is the 3D converter free?
Yes. There is no account, no file limit and no watermark. The conversion runs in your browser, so large files only depend on the memory of your device.
Are my files uploaded?
No. Files are read and converted locally in your browser with three.js. Nothing is sent to a server, the page works offline once it is loaded.
Which conversions are possible?
Every supported input (GLB, glTF, FBX, OBJ, STL, PLY, 3MF, DAE) can be written as GLB, glTF, OBJ, STL, PLY or USDZ. The table above shows what each output format keeps.
Why can I not convert to FBX?
There is no reliable FBX writer that runs in the browser. A half working FBX causes more trouble than it solves, so the converter does not offer it. All models in the Grab3D library come with a ready FBX file.
Can I convert many files at once?
Yes. Drop several files, folders or ZIPs. Each model gets its own row with a status, Convert all processes them one after another and All as ZIP downloads every result in one archive.
Why is my converted model the wrong size?
Some formats have no unit. OBJ and STL store plain numbers, so the converter needs to know what they mean. Check the dimensions in the info panel and set the unit of the source if the size is off.