Convert STL to 3MF
Convert a STL file to 3MF in your browser. Free, no upload, no sign-up.
Convert STL files to 3MF directly in your browser. The converter parses the STL mesh, rebuilds it in memory and writes it out as 3MF, keeping every triangle. Nothing is uploaded, there is no file size limit beyond your computer's memory, and the result downloads instantly. 3MF records the unit and can hold several objects with colors, so the model opens in the slicer at the right size without guessing.
How to convert STL to 3MF
- 1Drop your STL file
Drag a .stl file onto the box above or click to choose one.
- 2Check the preview
The model renders in 3D so you can confirm it loaded correctly. Dimensions, volume and triangle count are shown next to it; open edges are flagged if the mesh is not watertight.
- 3Download the 3MF
Adjust the export options if needed and click download. The exported file declares millimeters as its unit and contains the mesh as a single object.
What is a STL file?
STL is the oldest and most widely supported 3D printing format. It stores nothing but a list of triangles, with no color, texture, unit or scale information. Every slicer and almost every 3D tool can read it, which is why it is still the default exchange format for printable models.
Commonly used by: 3D printer slicers (Cura, PrusaSlicer, Bambu Studio), CAD export, Thingiverse / Printables
What is a 3MF file?
3MF is the modern replacement for STL, published by the 3MF Consortium (Microsoft, Autodesk, HP, Prusa and others). It is a ZIP archive containing XML that stores units, colors, materials, multiple objects and print settings. Slicers such as Bambu Studio and PrusaSlicer use it as their project format.
Commonly used by: Bambu Studio, PrusaSlicer, Cura, Windows 3D Builder, Fusion 360
3MF records the unit and can hold several objects with colors, so the model opens in the slicer at the right size without guessing.
STL vs 3MF
| STL | 3MF | |
|---|---|---|
| Full name | Stereolithography | 3D Manufacturing Format |
| Encoding | Text or binary | ZIP container |
| Geometry type | Triangle mesh | Triangle mesh |
| Colors | No | Yes |
| Textures | No | Yes |
| Materials | No | Yes |
| Stores units | No | Yes |
| Multiple objects | No | Yes |
| Typical use | 3D printer slicers (Cura, PrusaSlicer, Bambu Studio), CAD export, Thingiverse / Printables | Bambu Studio, PrusaSlicer, Cura |