Free Online STL Converter

This is our free-to-use STL file conversion tool that can be used to convert your STL file into any number of other 3D model formats. Our STL converter will extract the 3D model geometry contained within your file and accurately convert it to the desired format without any loss of detail. Our STL converter also has a batch processing mode whereby you may upload up to a maximum of 20 files to be converted in one go.

Drag and drop your files here to upload or click the button above.
A maximum of 20 files can be converted at once.

Please note: Your STL file file, when uploaded to our server, will be deleted 15 minutes after upload. Please download your converted STL file file before this time.
Our STL conversion tool supports converting to the following file types:

Our STL converter will extract the vertices, faces, and other geometric data that forms the structure of your 3D model and convert it to the requested format. If the selected format supports external texture files, these can be uploaded along with your STL model file, and these will be processed accordingly.

STL file information

Full NameStandard Triangle Language
Type3D Model
Mime Typeapplication/

The STL file format is used for storing 3D models and is a common format for distributing 3D printable models. STL files emerged in the 1980s as a format for storing a 3D mesh as a simple list of triangles. Due to its age and simplistic format, it has gained widespread support within 3D modeling and CAD applications.

As a result of the simple file format and its widespread support amongst 3D editors, the STL format has found itself as the format of choice for the distribution of 3D printable objects. There are many websites that offer 3D printing downloads in the STL format.

Mesh Geometry

As mentioned, STL files make use of a simple structure for containing the 3D mesh data. The 3D model is stored as a continuous list of triangles, with each triangle containing three vertices specifying the location in 3D space of the triangle, which, along with a single vector normal, is all that is required to render the model contained within the STL file. There are two formats of STL files: plain text and binary. When used with large and complex 3D models, the text format leads to very large file sizes and should be avoided, with the binary format offering more efficient storage of the mesh data.


The original STL format does not contain provisions for storing any kind of material, color, or texture information, meaning an STL file should be avoided if the model contains materials. There were two variations of the STL format created by VisCAM and SolidView that allowed for some limited color information to be stored with each triangle; however, this was not adopted by many STL renderers, so these formats are largely ignored.

STL Converter Capabilities

As materials containing color information is supported by the STL format, our tool will do its best to include this in the converted file.

Popular STL Converter Tools

How to Convert your STL file Online?

Here are 3 simple steps to convert your STL file using our free STL file file conversion tool.

Upload your STL file

Click the "Select File" button, and then select a STL file file to upload. The maximum file size is 100MB.

Select file type

Select the file type to convert your STL file to using the list of available types.

Download your file

Click the download link to get your converted file.

Frequently Asked Questions

Is it free to use the STL file conversion tools?

Yes, there is no cost to using our conversion tools.

Are there any STL file conversion limits?

At this time, we do not have any usage limits other than the maximum of 20 file uploads per conversion run.

How long do I need to wait for my converted file to be completed?

The size of your STL file will affect processing times, so please allow for this. For smaller files of around 5MB, our tools will aim to have it completed within a few seconds.

How is my STL file converted, whats involved?

When you upload your file to our site, we use a set of bespoke conversion components to, as accurately as possible, convert your file to the requested format. When the conversion is complete you will see a download link with which to retrieve your converted file.

Is the STL format suitable for 3D printing?

Yes. 3D printing slicer software generally supports the STL format without the need for conversion.

Is it safe to convert my STL on

Yes, your files are automatically deleted from our servers after 15 minutes.

Can I convert my STL file using Android, iOS, Mac OS or Linux?

Yes, you can. Our STL file converters only require a modern web browser to convert your files.

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