OBJ to STEP Converter

Convert a Wavefront .obj into a STEP file for CAD. Each object in the OBJ becomes a body; watertight meshes become solids.

How to convert OBJ to STEP

Drop the .obj above (the .mtl is not needed for STEP).
Check the size shown under the 3D view: OBJ has no units, values are taken as millimetres.
Keep STEP selected and click Download STEP.

Good to know

OBJ files from 3D scanners and sculpting apps are often very dense. STEP stores each triangle as a face, so reduce such meshes before converting (about 200,000 triangles at most).
Models made in metres or inches arrive too small or too big — scale them in CAD.
The faces stay flat; the model is not turned into smooth CAD surfaces.

Frequently asked questions

My OBJ comes out as a surface, not a solid.

The mesh is not closed. Scans and game models often have holes; repair the mesh and convert again.

Are my files uploaded?

No. Conversion runs in your browser.