Open a 3MF file online
3MF is a ZIP-based manufacturing format that stores printable meshes, units, colours, materials and build information. Preview supported 3MF geometry privately before opening a slicer or sending a job to print.
Interactive viewer — This format is parsed and rendered in the browser.
Drop a 3MF file to open it
or click to choose — everything stays on your device
Choose file🔒 100% private — files never leave your browser
Or turn 3MF into an image — snapshot the preview, add arrows or notes, and download a PNG.
What is a 3MF file?
3MF is a ZIP-based manufacturing format that stores printable meshes, units, colours, materials and build information. Preview supported 3MF geometry privately before opening a slicer or sending a job to print. The .3MF extension identifies a 3D Manufacturing Format file, which is served with the model/3mf media type. You can open it here instantly — drop the file into the box above and it renders in your browser. Nothing is uploaded.
The 3MF standard was designed to carry more reliable manufacturing information than a plain STL, including declared units, multiple objects, colours and a build plate arrangement. This viewer reads the package locally and renders the supported meshes for a quick visual check before slicing.
Besides this free online viewer, you can open 3MF files in desktop apps such as PrusaSlicer, Cura, Microsoft 3D Builder — but here all you need is a web browser.
Quick facts
| Format | 3MF — 3D Manufacturing Format |
|---|---|
| File extensions | .3mf |
| MIME type | model/3mf |
| Developer | 3MF Consortium |
| Category | 3D, CAD & GIS |
| Also opens in | PrusaSlicer, Cura, Microsoft 3D Builder |
Common uses
- Confirm that every printable object is present
- Check orientation and approximate build arrangement
- Preview a received 3MF file before opening Cura or PrusaSlicer
What this browser preview can and cannot show
A visible mesh does not prove that a model is watertight, manifold or printable. Production, beam-lattice, slice, secure-content and vendor extensions may not be interpreted. Always run the final file through the target slicer and printer profile.
Tips for a reliable preview
- Use 3MF units instead of relying on assumed STL scale
- Repair non-manifold geometry in a modelling or slicing tool
- Verify supports, layer settings and material assignments in the slicer
How to open a 3MF file online
- Click Choose file above, or drag your 3MF file onto the box.
- The right viewer loads automatically and renders your file.
- Read, scroll or page through it. To open a different file, choose Open another file.
100% private — files never leave your browser.
Libraries used to render 3MF in the browser
This viewer is built entirely with open-source JavaScript that runs in your browser:
Frequently asked questions
What is a .3MF file?
A .3MF file is a 3D Manufacturing Format, identified by the model/3mf media type. You can open and read it instantly in the viewer above without installing anything.
What programs open 3MF files?
On the desktop, 3MF files typically open in PrusaSlicer, Cura, Microsoft 3D Builder. Online, this page opens them in any modern browser — nothing to download.
How do I convert 3MF to an image?
Use Snapshot to capture the 3MF preview, optionally add arrows, text or highlights, then download it as a PNG image.
Does this viewer test whether a 3MF model can be printed?
No. It provides a visual preview. Printability, supports, tolerances and machine settings must be checked in a slicer.
Is it safe to open my 3MF file here?
Yes. The file is read and rendered entirely by JavaScript inside your own browser. It is never uploaded to a server, so nothing leaves your device.
Do I need to install anything to view a 3MF file?
No. There is nothing to install and no account to create. Open the page, drop your file, and it displays instantly.
Does it work on my phone or iPad?
Yes. The viewer is fully responsive and works in modern mobile and tablet browsers such as Safari and Chrome.
Is there a file size limit?
There is no hard limit, but very large files depend on your device’s memory. Big files are processed in the background so the page stays responsive.