3dfileconverter.onlineSTEP to OBJ Converter
Convert STEP or STP to OBJ locally with adjustable tessellation precision. Preview CAD mesh parts and export geometry for Blender or other mesh editors.
Enable JavaScript to open a model and use the interactive workspace.
How do I use this tool?
- Choose a STEP file from your device.
- Preview your model and adjust the settings.
- Create your output and download the result.
What does this tool do?
STEP curves are tessellated into triangles. Choose the precision before opening a file, or reload it to apply a new precision. Assembly mesh positions are retained; CAD features are not.
What are the file limits?
Models are processed locally. Inputs are limited to 50 MB per file and 500,000 triangles after import. Individual operations may have lower limits described below. Performance depends on your device.
JavaScript, WebAssembly and WebGL are required for the interactive workspace.
How are models processed?
Mesh loading and rendering use Three.js. STEP import and tessellation use occt-import-js, based on Open Cascade. These sources describe the underlying libraries; this tool's supported features and limits are listed on this page.
Frequently asked questions
Can I convert both STEP and STP files to OBJ?
Yes. Both .step and .stp files use the STEP input route. Select a tessellation precision, open the file, preview the resulting mesh and export OBJ. To change precision after loading, reload the model with the new setting.
Does the OBJ preserve exact CAD curves?
No. STEP surfaces are tessellated into triangles. Fine precision follows curves more closely but creates more triangles and uses more memory. Sketches, exact surfaces and parametric history are not retained.
Will the parts of a STEP assembly keep their positions?
The imported mesh positions are retained in the exported geometry. This does not preserve assembly constraints or an editable CAD feature tree. Use Export parts if you need separate files for selected mesh parts.
Does STEP to OBJ export include a material file?
No. The OBJ export contains geometry and does not generate an MTL file or texture images. If the STEP importer reads basic part colors and you need to keep them, use STEP to GLB instead.