Step 1
Choose an OBJ file
Select a .obj mesh up to 100 MB. The model remains on your device.
Free · Private · Browser-based
OBJ to STL Converter Online
Turn Wavefront OBJ mesh files into slicer-ready STL output without installing desktop software. Objects are processed locally, and separate OBJ meshes remain separate STL parts.
Drop OBJ file here
or browse your computer
Max 100 MB · processed locally
Your OBJ file stays on this device. Geometry is processed locally and is never uploaded.
How to convert OBJ to STL
Step 2
Convert mesh geometry
The browser reads OBJ objects and triangulates polygon faces for STL output.
Step 3
Download STL output
Download one binary STL, or a ZIP when the OBJ contains multiple mesh objects.
OBJ and STL are different file formats
OBJ can store polygon faces, named objects, groups, material references, and texture coordinates. STL stores only triangles and surface normals. During conversion, polygon faces are triangulated while materials, textures, and OBJ-specific grouping metadata are not included in STL.
| Property | OBJ | STL |
|---|---|---|
| Geometry | Polygon mesh | Triangle mesh |
| Materials | MTL and texture references | Not supported |
| Best for | 3D modeling and interchange | Slicing and 3D printing |
OBJ to STL FAQ
Is the OBJ file uploaded anywhere?
No. OBJ parsing and STL generation run locally in your browser.
Will OBJ materials and textures appear in STL?
No. STL stores geometry only, so MTL materials, colors, UV coordinates, and texture images are not preserved.
What happens to OBJ polygons?
Faces with more than three vertices are triangulated because STL represents every surface as triangles.
Can one OBJ create several STL files?
Yes. When separate mesh objects are detected, the converter packages their STL files into one ZIP download.
Need the reverse conversion?
Convert an STL triangle mesh back into an editable OBJ mesh file.