WorkbenchA useful little toolbox.

STL to faceted STEP

Convert a closed triangle mesh into a faceted STEP solid.

Processed on your device. No file upload.
Choose a file to get started

Drop it here, or use the file picker.

How to use this tool

  1. Choose your file or try the example.
  2. Run the tool and check the result.
  3. Save the result where a download is available.

Supported features & limits

ASCII or binary STL, up to 20 MB and 20,000 triangles. Select the STL coordinate unit; output is millimetres. Requires one closed, orientable component with exact shared coordinates and nonzero volume. Rejects open/nonmanifold meshes and disconnected components. Corrects triangle winding; does not repair gaps, check self-intersections or rebuild cylinders, curves or CAD features. Each triangle remains a planar face. Local conversion, 90-second limit.

What happens to my files?

Your browser reads the file locally. File contents are not sent to our server. Closing or resetting this page clears the working result. Downloaded copies remain on your device.

Maintained by Roman Zmazhenko. Updated 1 November 2026.