Free Online STEP to STL Converter

You can use our STEP to STL conversion tool to quickly and easily convert your 3D model files for free. You may upload up to 20 files at one time, and our batch STEP to STL converter will process each 3D model and present you with a download link for each file once completed.

Select File(s)

Or drag and drop your files here to upload.
A maximum of 20 files can be uploaded at once.

Please note: Your STEP file, once uploaded to our server, will be deleted 15 minutes after upload, so please download your converted STEP file before this time.

Our 3D model STEP to STL tool will load your STEP file and, where supported, attempt to extract all the relevant 3D features, such as geometry, textures, and animations. To access the 3D conversion configuration options, click the button when you have selected your files. The current options support the ability to voxelize your 3D model and more.

How to Convert your STEP to STL Online?

Here are two simple steps to convert your STEP to STL using our fast and free STEP converter tool.

Upload your STEP file

Click the "Upload a STEP File" button, then select a STEP to upload. The maximum file size is 100MB.

Download your STL

Click the download link to receive your STL file.

Frequently Asked Questions

How can I convert my STEP file to STL?

First, click the "Upload..." button and select your STEP file to upload. Your STEP file will be uploaded to our servers. When the STEP to STL conversion has completed, you can download your STL file right away.

How long does it take to convert my STEP to STL?

We aim to process all STEP to STL conversions as quickly as possible; this usually takes around 5 seconds; however, this can be longer for certain files, so please be patient.

How accurate is the STEP to STL conversion?

We aim to provide the best conversion experience. Our tools are under constant review and development, with new features being added every week.

How does converting STEP to STL work?

In order to successfully convert an STEP formatted file to the STL format, our converter tools will perform several initial checks to ensure the file provided is indeed an STEP file. There are many files out there where the file type extension does not match the data contained within the file. Along with these file type checks, our tools will do additional checks to ensure the file is correctly formatted to match the provided file type. There are many tools out there that do not always create STEP files to the exact specification.

Take your STEP file

The STEP file format is a text-based format, meaning its contents are human-readable, making STEP files straightforward to edit in simple text editors. Within this text-based format are the core elements that make up the 3D model, including points, lines, edges, faces, and more. To ensure efficient conversions, our tool will check all data that is contained within the STEP file and remove any information that is duplicated. STEP files are notoriously slow to process, even on high-end computer systems, which is why our STEP to STL converters have been hand-optimized for speed making our STEP converters the fastest available.

Convert the data from STEP to STL

Now that the data from the STEP file has been processed, our tool can apply any conversion specified options, such as enabling Voxel mode, and with these applied, prepare the data to be converted to the final STL file format. Part of this process ensures checking the capabilities of the STL format and removing any data that cannot be represented.

Save to the STL format

At this point, the STEP to STL conversion tool will have the 3D model in a state that is ready to be transferred to the STL format. Our tool creates the STL file, ensuring all the model data is present and is formatted to match the STL file specification to ensure the file opens in compatible STL file editors. To ensure a compact file size, our STEP to STL converter will always save the STL file in a binary format.

File format information for STEP and STL

Extension	STEP
Full Name	STEP-File
Type	3D Model
Mime Type	application/octet-stream
Format	Binary
Opens With	CAD Assistant

STEP files are a 3D file format used to store complex 3D object definitions in a standard format to facilitate data transfer between compatible 3D modelling and CAD (Computer Aided Design) applications. In addition to storing 3D object data, the STEP format can store additional information such as materials, tolerances, and other relevant data.

The STEP format was first released in the early 1990's, has become a standard for 3D object storage, and is used in automotive, electronics, and other industries. STEP files can be opened in most modern CAD applications and can be imported into many 3D modelling applications too.

The file content is ASCII text-based and conforms to the ISO-10303-21 standard. The 3D object contained within the STEP file is described using a combination of points, lines, and edges. Due to the format being ASCII text, complex objects can lead to large file sizes. In addition to large file sizes, some complex STEP files can take a long time to open within editing applications, even on a high-spec, modern computer.

STEP Converter Capabilities

When converting 3D model or mesh files using our STEP converter, we will attempt to convert colour materials into a suitable format for use in the converted file.

Extension	STL
Full Name	Standard Triangle Language
Type	3D Model
Mime Type	application/vnd.ms-pki.stl
Format	Text
Opens With	Blender, MeshLab, CAD Assistant, DAZ Studio

The STL, or Standard Triangle Language, file format has been around since the '80s and is supported by most modern 3D modelling applications. In particular, the STL format has become something of a standard format within the area of 3D printing, despite the rise of more modern formats such as 3MF.

STL files come in two flavours: binary or text format. The text format is human-readable, making it easy to perform manual edits, but can lead to very large file sizes. As you can imagine, the binary format is much more compact and represents the majority of the STL files you are likely to encounter.

The format itself is very simple; the 3D model is represented by a sequential list of triangles, with each triangle defined with 3 points consisting of their X, Y, and Z positions, along with an additional vector that contains the face normal (the direction the face is pointing). There is an additional attribute block for each triangle; however, this is largely unused and thus unsupported.

STL Converter Capabilities

When converting your STEP to STL, our tool will attempt to accurately convert any colour or material information.

Information for converting from STEP to STL

Your STEP file will be converted to a STL file using our unified 3D model and mesh conversion tool. Our STEP 3D tool performs accurate conversions of 3D elements such as vertices, faces, normals, and relevant material information. As both STEP and STL support colour material information, our tool will also attempt to convert the colour information.