Free online STEP to AMF converter

Source format

AMF usually refers to Additive Manufacturing File, a 3D printing file format designed to describe printable objects with more detail than older formats such as STL. It is used by 3D printing software, CAD tools, and slicers to store geometry, color, materials, and sometimes lattice or texture information. AMF is most common in workflows where a model must be prepared for additive manufacturing and where richer object data is useful.

Target format

The most common conversion target for AMF is STL, another widely supported 3D model format used by slicers and printers. STL is popular because it is simple, broadly compatible, and supported by nearly every 3D printing application. Its main advantage is ease of use and universal acceptance, though it does not preserve advanced data such as color or materials. In some workflows, AMF may also be converted to 3MF for better modern 3D printing support.

How to perform the conversion

The best method depends on whether you want to preserve advanced AMF features or simply make the model usable in a broader set of tools.

1. Open the AMF file in a 3D application or slicer. Programs such as PrusaSlicer, Ultimaker Cura, MeshLab, or Blender can import AMF in many cases.
2. Check the model after import. Make sure the geometry appears correctly and that scale, orientation, and units are as expected.
3. Export or save as the target format. Use File → Export or File → Save As, then choose STL if you want maximum compatibility, or 3MF if you want to keep more modern printing data.
4. Confirm export options. If the software offers binary or ASCII STL, choose binary STL for smaller files unless a specific workflow requires ASCII.
5. Verify the output. Reopen the exported file in your slicer or viewer to confirm that the mesh is intact and ready for printing.

If you prefer command-line workflows, MeshLab and some CAD tools can be scripted or batch-processed, but the exact commands depend on the software and version. For most users, a desktop slicer or 3D editor is the most reliable route.

Notes on quality and limitations

AMF can store more information than STL, but that extra information is often lost when converting to STL. If your AMF file includes colors, materials, or multiple objects, expect those details to be discarded unless you convert to a format that supports them, such as 3MF. Also, some applications only support a subset of AMF features, so imported models may differ slightly depending on the software used.

For printing, the most important checks are watertight geometry, correct units, and proper mesh repair. If the model has errors before conversion, those issues may carry over into the exported file and affect slicing or print quality.