Free 3MF to STL converter
And STL to 3MF, for any slicer

Drop a 3MF file from Bambu Studio, PrusaSlicer, Cura or Windows 3D Builder and save it as STL, or drop an STL and save it as 3MF, with the size and a watertight check shown before you download.

The conversion runs in your browser, so the file never leaves your computer.

Drop a 3MF or STL file here or choose a file. 3MF from Bambu Studio, PrusaSlicer, Cura and 3D Builder, or STL to turn into 3MF. OBJ, STEP and other 3D files work too.

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Free, no sign-up. Your file stays on your computer. It is opened and converted in this browser tab and is never uploaded to us or anyone else.

3MF to STL, OBJ or GLB, and STL to 3MF
Every part kept, size shown in millimetres
Watertight check before you print

How it works

How to convert 3MF to STL

3 steps, and the file never leaves your computer.

1. Drop the file

Drop a .3mf file, or a .stl if you want a 3MF. It opens in 3D with its size in millimetres and whether every part is closed, which is what a slicer needs.

2. Choose the format

Pick STL for any slicer or printer service, 3MF to keep the parts as separate objects in Bambu Studio or PrusaSlicer, or OBJ and GLB for 3D programs.

3. Download

Binary STL is the smallest. A 3MF from several parts keeps each part as its own object, so you can arrange them on the plate.

3MF vs STL

3MF vs STL: what each file holds

And what changes when you convert between them.

What a 3MF holds

3MF is a ZIP package from the 3MF Consortium. Besides the mesh it can hold colours, materials, several objects, their position on the plate and, in slicer project files, the print settings.

What an STL holds

STL holds only triangles: no units, no colours, no materials and no settings. Every slicer and printing service reads it, which is why it is still the common format.

What is lost in 3MF to STL

Colours, materials, print settings and the plate layout stay behind. The shape of every part comes across exactly. A multi-colour print needs one STL per colour.

Why go from STL to 3MF

3MF stores millimetres, so a part never comes in 25 times too small, and it keeps several parts as separate objects in one file. Bambu Studio and PrusaSlicer save 3MF by default.

From part to images

What we make from 3D files

Product designers and manufacturers send us their CAD and mesh files to be turned into images that sell the product before the first one is made.

3D product rendering

Photoreal studio and lifestyle images of your product, made from its 3D file.

See product rendering

3D modeling

Clean models built from drawings, sketches or a rough mesh.

See 3D modeling

Architectural visualization

Photoreal images of buildings and interiors, with your product placed in them.

See architectural visualization

3MF to STL FAQ

Questions about 3MF and STL files

The formats, what is lost, slicers and privacy.

Ask us a question

What is a 3MF file?

3MF (3D Manufacturing Format) is a 3D printing file from the 3MF Consortium. It is a ZIP package that holds the mesh in millimetres, and can also hold colours, materials, several objects and, in slicer project files, the print settings. Bambu Studio, PrusaSlicer, Cura and Windows 3D Builder all save it.

3MF or STL: which is better?

For printing on your own printer, 3MF: it keeps units, parts and settings. For sending a part to a printing service or another program, STL is still the format everyone reads.

Does the STL keep the colours and print settings?

No. STL has no place for them, so only the shape comes across. Every part of the 3MF is kept and saved together in one STL. For a multi-colour print, export one STL per colour from your slicer.

Can I open a Bambu Studio or PrusaSlicer project 3MF?

Yes, the models in it open and convert. The print settings stored in the project are only read by that slicer and are not carried into the STL.

Is my file uploaded?

No. The file is opened and converted in this browser tab on your own computer and is never sent to us or anyone else. It is free, with no sign-up.

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Projects completed

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Architects, developers & interior designers.

Working for 215 companies since 2013.

125 of 220 clients came back.

More than half of our clients have hired us again.