Convert OBJ to STL online — free, no signup, no upload
OBJ is a common mesh format; STL is what 3D-printing slicers expect. This converter reads the .obj geometry and writes a clean binary .stl with the same triangles. This converter runs entirely in your browser: your file is read on your device, converted, and downloaded — it is never uploaded to a server.
How to convert OBJ to STL
1. Drag your file onto the box above, or click Open OBJ file. 2. Preview the model in 3D to confirm it's the right one. 3. Click Convert to STL & download — the new file saves straight to your device.
Frequently asked questions
How do I convert OBJ to STL?
Drop your .obj above or click Open, preview it, then click Convert to STL & download. Everything runs in your browser.
Do I need the .mtl file?
No — STL stores only geometry, so materials aren't needed. The mesh converts from the .obj alone.
Is my OBJ uploaded?
No. The conversion is fully client-side; your file stays on your device.