The Bottom Line First
**Use 3MF if your slicer supports it.** It stores more information, preserves print settings, and is the direction the industry is moving.
**Use STL if you need maximum compatibility** — it works with literally every slicer and 3D viewer ever made.
What's in an STL File
An STL file contains one thing: the triangle mesh that defines the shape of the model. That's it. No color, no scale, no recommended settings, no metadata.
Every time you open an STL file, your slicer starts fresh with its own defaults. If the designer intended the model at a specific scale or orientation, that information isn't in the file — it's in the description.
What's in a 3MF File
A 3MF file is a ZIP archive containing:
When you open a well-made 3MF file in a compatible slicer, you get the model already oriented correctly, at the right scale, with suggested layer height and infill baked in. You just click slice.
Practical Comparison
| Feature | STL | 3MF |
|---|---|---|
| Universal compatibility | ✅ Yes | ⚠️ Modern slicers only |
| Preserves scale | ❌ No | ✅ Yes |
| Preserves orientation | ❌ No | ✅ Yes |
| Includes print settings | ❌ No | ✅ Yes (slicer-dependent) |
| File size | Larger | Smaller (compressed) |
| Good for sharing | ✅ Widest reach | ✅ Better experience |
Which Slicers Support 3MF?
All major modern slicers:
Older or more obscure slicers may only support STL. If you're using something unusual, stick with STL.
What Bodhin Industries Provides
All products include STL files. Most also include 3MF files where available. When a 3MF is provided, it includes the recommended orientation. Open it in Bambu Studio or PrusaSlicer and you'll see the model already set up to print correctly.
If you're new to 3D printing: use the 3MF file. It removes one more variable.