3DM to STL Converter
Drop a .3dm file below and get a .stl back. The conversion happens inside this page using WebAssembly, so nothing is uploaded to a server and there is no queue to wait in.
- Private by designFiles stay on your device.
- No queueConversion starts instantly.
- No sign upNo account, no limits per day.
Compatibility
What survives the trip from 3DM to STL.
| Feature | 3DM | STL | Result |
|---|---|---|---|
| Geometry | Supported | Supported | Supported |
| Vertex colors | Supported | Not supported | Not supported |
| Materials | Partial | Not supported | Not supported |
| Textures | Not supported | Not supported | Not supported |
| Scene hierarchy | Supported | Not supported | Not supported |
| Animation | Not supported | Not supported | Not supported |
How to convert 3DM to STL
- 1Add your 3DM fileDrop the .3dm file into the box, or pick it from disk. Multiple files are converted one after another.
- 2Pick STL as the outputSTL is already selected on this page. Adjust scale, up axis or triangle budget if the target application is picky.
- 3Download the resultThe .stl file is written locally and appears as a download button next to your file.
About 3DM
3DM is the openNURBS based native format of Rhino. It stores NURBS surfaces, meshes, layers, blocks and object attributes, and the openNURBS toolkit makes it one of the few native CAD formats that is genuinely readable outside its host application.
- Rhino
- Grasshopper
- Revit via plug-in
- Blender via add-on
About STL
STL stores a model as a flat list of triangles with no units, colors or scene structure. Its simplicity is exactly why every slicer and every 3D printer on the market reads it, and why it is still the default export target for mechanical parts.
- Cura
- PrusaSlicer
- SolidWorks
- Fusion 360
- Blender
Questions
Is this 3DM to STL converter free?
Yes. There is no account, no daily quota and no watermark. The tool is a static web page and the work is done by your own CPU, so there are no server costs to pass on.
Are my files uploaded anywhere?
No. MeshFormat loads a WebAssembly build of the geometry kernels into your browser and reads the file locally. You can open the network tab and confirm that nothing leaves the page, or disconnect after the page has loaded and keep converting.
How large can a 3DM file be?
The practical limit is your available memory rather than an arbitrary cap. Models up to a few hundred megabytes work on a normal laptop; very dense scans convert faster if you lower the triangle budget in the options.
What is lost when converting 3DM to STL?
Vertex colors: vertex colours are dropped because the output format has nowhere to store a colour per vertex. Materials: material definitions are dropped, so the model arrives with a single neutral surface. Scene hierarchy: the scene tree is flattened, so parts arrive as a single level list rather than nested groups.
Which programs open STL files?
Cura, PrusaSlicer, SolidWorks, Fusion 360 and most other tools that work with 3D meshes read .stl directly.