3MF Converter
FileFlip converts 3MF files into 13 other formats entirely inside your browser, using Assimp compiled to WebAssembly. The 3MF file is never uploaded to a server: it is read off your disk, converted on your own machine, and saved back by the browser. There is no file-size limit and no account to create.
How do I convert a 3MF file?#
- Drop your 3MF file onto the converter at the top of this page, or click it to pick one from your computer.
- Choose the format you want out of it. FileFlip downloads the engine that conversion needs, once, and your browser caches it.
- Conversion starts the moment you pick the format, and the result is yours to download. The work happens in this tab, so nothing is uploaded and nothing is queued.
Is it safe to convert 3MF files online?#
Yes, because nothing is uploaded. FileFlip converts 3MF files inside the browser tab you already have open, using WebAssembly builds of the same engines a desktop converter would install. Your file is read from your own disk into the page's memory, and no request carrying it is ever made.
You do not have to take that on trust. Open your browser's network panel, run a conversion, and you will see the engine come down and your file go nowhere. There is no upload, no server-side copy, no retention window, and no account tied to what you converted.
How FileFlip works lists every engine, its version and its download size, and shows how to check for yourself that nothing leaves your machine.
What happens to a 3MF file#
FileFlip converts 3MF into 13 formats with Assimp, all of it inside the browser tab. Each conversion below names the engine it uses, what it downloads, and exactly what that conversion keeps or drops.
| Category | 3D Models |
|---|---|
| File extension | .3mf |
| FileFlip support | Read and written |
| Conversions available | 13 |
| Engines | Assimp |
| Downloaded to your browser | 11.2 MB on the first conversion, then cached |
What is a 3MF file?#
A 3MF file is a ZIP archive of XML documents, published by the 3MF Consortium in 2015 as 3D printing's replacement for STL, adding the colour, material, unit and multi-object placement data STL never had.
Use 3MF over STL whenever colour, material or multiple positioned objects need to travel with the geometry to the printer.
Convert 3MF to STL only when the destination software is old enough to not support 3MF at all.
The 3MF file format reference covers the specification, the programs that open one, and what each conversion keeps or drops.
3MF questions people ask#
What is a 3MF file?
A 3MF file is a 3D printing format, a ZIP archive of XML, published by the 3MF Consortium in 2015 to replace STL. It adds colour, material, real-world units and multiple objects with their placement on the build plate, none of which STL can store.
Is 3MF better than STL?
3MF can carry colour, material, units and multiple positioned objects in one file, all of which STL simply has no fields for. STL still has broader support since it's decades older, so the better choice depends on whether the printer and slicer being used actually support 3MF.
Can I open a 3MF file with a ZIP tool?
Yes, a 3MF file is literally a ZIP archive containing XML documents, so any standard archive utility can open it and show the files inside. That doesn't render the model, but it does let you inspect the raw geometry and metadata directly.
Does my 3D printer support 3MF?
Most current slicers, including PrusaSlicer, Cura and Bambu Studio, read 3MF natively and it's become the default project format for several of them. Older or budget slicer software may still expect STL, so it's worth checking a specific printer's software before relying on 3MF alone.