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STL to 3MF converter
Use the STL to 3MF converter online to keep supported triangle geometry in a model container with explicit units. Review the dimensions before saving; this is not a recovered slicer project.
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FROM FILE TO FINISHED MESH
How to convert your file
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Choose the right mode, scale and detail. Processing runs in your browser.
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Rotate the preview, save the output and verify it in your next application.
Convert an STL file to 3MF: check units and the model container
For STL to .3MF output, choose the STL, review its size and keep 3MF as the output format. An STL does not record real-world units, so confirm how its numeric coordinates should be interpreted. The STL 3MF converter cannot recover original colors, materials, assemblies or print settings from triangles alone.
To learn how to convert STL to 3MF reliably, reopen the downloaded model in the target slicer and compare a known dimension. Save the original STL and a separate slicer project if you need to retain machine settings.
Understand core 3MF models and slicer projects · Use the reverse 3MF to STL conversion
Processing limits
STEP input: 20 MB. STL, OBJ and 3MF input: 50 MB. Output is limited to 1.2 million triangles. Complex models may need simplification in the source application.
One file at a time. Processing stops after 90 seconds. Files remain in browser memory, and no conversion upload is performed. Replacing a file clears the previous result. Closing the tab releases its working data.
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