STL to OBJ converter
Drop an STL file and get an OBJ back in seconds. STL is triangles only, used mostly for 3D printing slicers. OBJ is plain text, read almost everywhere, the usual choice for older 3D software and CAD-adjacent tools. The conversion runs entirely in your browser, so your file never leaves your device.
Choose a file to see its details here. Nothing is uploaded: everything runs in your browser.
How to use the stl to obj converter
- 1Choose your STL fileDrag it onto the panel or click to browse. It's read locally and never uploaded.
- 2Check the previewOrbit the model and check the triangle count, size and materials before converting.
- 3Download the OBJExport a OBJ with one click. Downloads are included with every plan.
What carries over
- STL has no colour or materials, so the OBJ gets a neutral grey material you can restyle.
- STL is Z-up, so the model is turned Y-up on import and keeps its orientation in the OBJ.
- Units: STL is unitless (slicers assume millimetres) and OBJ is unitless. Numbers are copied 1:1, so check the size in the target app.
STL vs OBJ
| STL | OBJ | |
|---|---|---|
| Full name | stereolithography mesh | Wavefront OBJ |
| Appearance | no colour or materials | basic materials in a separate .mtl file |
| Animation | No | No |
| Units | unitless (slicers assume millimetres) | unitless |
| Best for | 3D printing slicers | older 3D software and CAD-adjacent tools |
Questions
- Is my STL file uploaded?
- No. The STL is parsed and the OBJ is written by JavaScript in your browser tab. The file never reaches our servers.
- Will the OBJ look the same as the STL?
- The geometry is identical. OBJ holds basic materials in a separate .mtl file, so surface appearance changes. See the notes above for this exact pair.
- Is there a file size limit?
- Files up to 150 MB open, but very large models depend on your device's memory. Desktop browsers handle big files best.