How to convert STL to STEP using FreeCAD

This tutorial covers how to convert an STL to a STEP using FreeCAD.
Note: Since STLs are meshes, the resulting model won't be as precise as parts originally made as solids.

FreeCAD can export:
- Step
- Iges
- Scad
- Dxf
- Dwg
- Obj
- Pdf
And many others…

  1. Step 1: Install FreeCAD

    To start off, make sure you have FreeCAD downloaded and installed

  2. Step 2: Import STL

    Open your STL part in FreeCAD

    Go to "Part" workbench

  3. Step 3: Convert from Mesh to Shape

    Now, select the imported STL part in main view or the model tree.

    Go to Part / Create shape from mesh...

    Set your mesh sewing tolerance in the pop up window

    FreeCAD will now create a new shape in the model tree


    • There will be no analyzing or validating of the mesh object.
    • Analyzing and repairing of the mesh (if needed) should be done manually before conversion.
    • Appropriate tools are available in the Mesh Workbench.

    If you're looking for a fast solution to get a Step exported now would be the time to export it. However, if you want a less triangulated solid or Boolean operations performed, then follow these next steps...

  4. Step 4: Simplify Shape

    So you now have a shape to work with but as you can see there's still allot of triangulated faces

    To simplify this part, now select the shape and go to Part / Refine shape

    Yet another part will be added to your model tree, now simpler!

  5. Step 5: Convert Shape to Solid

    Now, to convert the shape to a solid that Boolean operations can be performed on...

    Select your now simplified part and go again to the Part menu, this time selecting "Convert to solid"

    And one more time a new solid will show up in your model tree

    Quick Tip: Selecting a part in the model tree and pressing space will hide that selected part. This makes it easier to see the newly made shape. Hidden parts will now appear greyed out as seen in the above picture.

  6. Step 6: Export

    Select the model you want to export, in this case the fourth part in the model tree

    File / Export

    And you're done! You now have a Step file from a STL file!

  7. Step 7: Resources

    STL to solid conversion:

    Working with meshes in FreeCAD:

    Prusa LCD stand: