Convert 3MF to STL for free

How to Convert your 3MF to STL Online?

Here are two simple steps to convert your 3MF to STL.

Upload a 3MF

Click the "Upload a 3MF File" button and select a 3MF to upload. The maximum file size is 100MB.

Download your STL

Click the download link once completed to receive your STL file.

A Comparison of 3MF and STL File Formats

Here we will do a comparison of both the 3MF and STL file formats to see which format is the most suitable to use in different scenarios. Although both formats are a popular choice when wishing to 3D print an object, each has different capabilities, which may influence your decision as to which one to use.

Before we begin, it's important to remember that the STL format has been around since the 1980s and was never designed to be used as a 3D printing format. It gained popularity in the early days of consumer 3D printing due to the format's simplicity and widespread support among 3D modeling software.

Structure

Although both formats are capable of storing complex 3D objects, they both go about it in very different ways. A 3MF file is capable of storing the model geometry in a highly efficient manner, whereby you have a single list of vertices and texture coordinates. From these, the faces that make up the 3D model reference them without any duplication of data. An STL file does not do this; in the STL format, each face in the 3D object has its own set of 3 vertices that cannot be re-used by other faces.

Whilst STL files are able to store a face normal, essentially the direction the face is pointing, the 3MF format does not support face normals as these can be calculated automatically with some clever math as explained here.

Supported Material

When it comes to materials, the STL format is incapable of storing face colors, materials, and textures. It is true that some vendor-specific versions of the STL format included some limited support for face colors; however, as these are not part of the STL standard specification, they will be ignored. The 3MF format, on the other hand, was designed from the start to support materials and textures, with material definitions that include color information included in the same file as the 3D object geometry. Also included within the 3MF file will be any necessary texture files, which helps when transmitting a 3MF file as all the textures needed are included and cannot be lost, as is the case with certain 3D model formats such as OBJ that store textures and materials as external files.

A custom laptop design in STL format

A cog in a Replicator 3D printer

A complete 3D-printed Pokémon Go Gym

Editing

From our experience, editing an STL file is easier than editing a 3MF file. This is mainly due to the fact that the STL format has been around a lot longer than 3MF and has widespread support within many 3D editing applications. Support for 3MF is growing, but at this time, STL files are easier to edit than 3MF files. As the 3MF format offers superior features compared to the STL format and is designed to store 3D printable objects from the start, support for it within 3D editors will only get better.

As for support amongst 3D slicer software, you will find that most slicers will support both STL and 3MF files.

File Size

When 3D objects are saved in the STL format, they are saved as a raw, uncompressed binary file, making the size of the resulting STL file much larger than when saving the same 3D object in the 3MF format. This is due to the 3MF standard using the ZIP file compression to store all the 3D model geometry, textures, and metadata.

Summary

To conclude this comparison, if you are intending to 3D print your 3D model, we would recommend the use of the 3MF file format for storing your model, provided that your 3D editing software and 3D printing slicer software support the 3MF format. If not, you can use our 3MF to STL file converter. Storing 3D objects in the 3MF format also ensures any textures and additional materials are stored within the same physical file and that the file size is kept to a minimum to help improve the speed of uploading and downloading your 3D model files.

File Format Information for 3MF to STL

Extension	3MF
Full Name	3D Manufacturing Format
Type	3D Model
Mime Type	application/vnd.ms-package.3dmanufacturing-3dmodel+xml
Format	Binary
Tools	3MF Converters, 3D Model Voxelizer, Create 3MF Animation, Compress 3MF, 3MF Asset Extractor, Text to 3MF, 3MF Viewer

Description

3MF files are a modern 3D file format designed specifically for use with 3D printable models (additive manufacturing). It was designed to be the successor to the popular legacy STL format (also a common format in 3D printing) to overcome the limitations of that format.

The format of 3MF files is XML-based and compressed with standard Zip file compression, resulting in small, easily transferable files. The format supports 3D meshes along with associated materials and textures, all contained within the Zip file.

3MF Notes

If your 3MF file contains textures, these will be included in the conversion process. If a material contains color information, this will be translated where possible.

Supported Features

Mesh geometry
Face and vertex colors
Textures

Extension	STL
Full Name	Standard Triangle Language
Type	3D Model
Mime Type	application/vnd.ms-pki.stl
Format	Text & Binary
Tools	STL Converters, 3D Model Voxelizer, Create STL Animation, Compress STL, Text to STL, STL Viewer
Open With	Blender, Daz Studio, MeshLab, CAD Assistant

Description

The STL file format has its roots in the 1980's and is the native file format for 3D Systems stereolithography CAD software. The format defines a triangulated mesh with vertices and faces and is a popular format for sharing 3D printable model files.

There were several formats that attempted to extend the STL format, namely SolidView and VisCAM, whose formats included limited 15-bit color information for each mesh face, which is often ignored by most modern 3D software. The STL format can be either text or binary; our tools will support both formats.

STL Notes

The standard STL file format does not support colored faces, vertices, or texture information. The STL file generated by the tool will contain only raw mesh/triangle data by default, which is perfect for 3D printing.

The tool also has the option to save the file to one of the non-standard formats that support colored faces, such as VisCAM and SolidView which is perfect if you want to further process the STL in software that supports these formats.

Supported Features

Mesh geometry
Face colors via the VisCAM and SolidView formats
Binary and text versions are supported

Comparing 3MF and STL Features

3MF Features

Mesh Geometry (Vertices and Faces)
Vertex Normals
Face Normals
Vertex Colors
Face Materials (Excluding textures)
Textures
Point Cloud
Multiple Objects Per File
Object Transforms (Translation, Rotation, and Scale)
Bones/Joints
Animations
Suitable for 3D Printing

STL Features

Mesh Geometry (Vertices and Faces)
Vertex Normals
Face Normals
Vertex Colors
Face Materials (Excluding textures)
Textures
Point Cloud
Multiple Objects Per File
Object Transforms (Translation, Rotation, and Scale)
Bones/Joints
Animations
Suitable for 3D Printing

How does it work?

Converting from the 3MF file format to STL can be a complex process and any tool used for this conversion process needs to be able to handle a variety of data conversion tasks as well as identify any defects within the 3D model and fix them. Here we will explain the conversion process used by our tool to accurately convert your 3MF file to a valid STL 3D model suitable for 3D printing. Lets start with the conversion process, which involves the following steps:

Step 1: Read the Source 3MF File

A 3MF file is a collection of 3D model data files including mesh and texture data compressed into a single file aimed at the 3D printing arena. The file is basically a ZIP file containing the relevant 3D files with the 3MF extension. The internal mesh structure is stored within various XML files making this easy to read in using a standard XML parser.

Our tool can read the compressed 3MF file and parse the 3D model contents taking into account all vertex, face and material information. As the 3MF format supports nested models within the 3D scene our tool will check for these and perform any world space transforms that are needed.

When our tool reads this 3D data, all we are interested in are the vertices, faces, and normals, as this is the only data that can be accurately converted into the final STL file.

The 3MF file can contain other data, such as material definitions and textures, that describe how a particular set of 3D geometry should be rendered. As we are creating an STL file, which does not support materials and textures, we will be ignoring this data if it is present in the 3MF file.

For more information regarding the 3MF file format, please see this great article that goes into a lot of detail explaining the 3MF format.

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Step 2: Process File Data

With the 3MF file data read, our tool generates an internal representation of the full 3D model and will attempt to fix any geometry issues encountered. Along with repairing any issues with the 3D model, the tool will remove any duplicated vertices and prepare the model for exporting to the STL format.

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Step 3: Saving to the STL Format

The STL format has been around for many years and has become not only a standard format for storing and transmitting 3D models but also a standard format for 3D printing, something we have talked about previously. STL files can be opened in most modern 3D editing applications without further processing.

To enable the saving of the model, our tool now needs to take the in-memory 3D model we have created in step 2 and convert this to the STL format. As the STL format supports only simple triangles with a single directional normal, if your 3MF contains vertex normals, these will be recalculated into a single-face normal. To ensure an efficient file size, our tool will always save any STL file in its binary format.

Frequently Asked Questions

What is an STL file?

The STL file format describes an unstructured triangulated surface of the triangles using a 3D Cartesian coordinate system. STL files do not contain any scale information, and the units are arbitrary. We have a more detailed description of an STL file here.

How long does it take to convert my 3MF to STL?

We aim to process all 3MF to STL conversions as quickly as possible, this usually takes around 5 seconds but can be more for larger more complex files so please be patient.

What STL formats can I convert to?

Our tool will save all STL files in binary format. Optionally, our tool will allow you to save to the non-standard color STL format.

Is it safe to convert my 3MF to STL on ImageToStl.com?

Yes, of course! We do not store the 3MF file you submit to us. The resulting STL file, once created is deleted 15 minutes after upload and the download link will expire after this time.

Do I need a high-spec. computer to use the 3MF to STL converter?

No. All our conversion tools process your 3MF file on our dedicated conversion servers, meaning you can use our tools on low-spec computers, laptops, tablets, and mobile devices and receive your converted STL file quickly.

Can I convert my 3MF to STL on Windows, Linux, Android, iOS or Mac OS?

Yes! Our 3MF to STL tool will run on any system with a modern web browser. No specialist software is needed to run any of our conversion tools.

What if I am using an Ad Blocker, will that affect things?

Yes. Although you can use an Ad Blocker, if you like our 3MF conversion tool please consider white-listing our site. When an Ad Blocker is enabled there are some conversion limits on some of our tools and processing/conversion times will be longer.

Can I get support with converting my 3MF to STL?

Yes. When you have converted your 3MF to STL, there is a "Feedback" option that you can use to let us know of any issues you encountered when converting your file.