Free online tool

Free Online BREP to STL Converter

Easily convert your .brep files to .stl format using our powerful online 3D CAD converter—no downloads or installations required.

Encrypted uploads
Auto-delete in 24hrs
Up to 300 MB

Drag & drop your 3D files here to convert

or click to browse files

Supported formats: .brep

Don't have a file? Try a sample:

Conversion quality notes (read before converting)

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HOW IT WORKS

How to convert BREP to STL online

No downloads. No plugins. Works right from your browser.

01

Upload your BREP file

Drag & drop or browse to select your .brep file

02

Select STL as the output format

Choose STL as your target CAD format

03

Convert and download instantly

Download your converted STL file in one click

Why use Marathon OS 3D CAD File Converter

Lightning-fast conversion

Convert in seconds with our cloud-based engine. No waiting.

No installation required

Works in your browser — no downloads or plugins needed.

Handles large & complex models

Optimized for large and intricate CAD files up to 300 MB.

Secure & private

Encrypted uploads. Files automatically deleted after 24 hours.

Your files, your IP

Full file ownership stays with you. We never share your data.

Available 24/7

Convert files anytime, anywhere — no restrictions.

Privacy and file handling

Encrypted uploads + secure processing

Files are encrypted during upload and processed securely.

Automatic deletion after 24 hours

Uploads are automatically deleted after 24 hours.

File ownership stays with you

You retain full ownership of your files.

BREP

Boundary Representation, which is a method used in computer-aided design (CAD) and 3D modeling to represent the shape of a 3D object. BREP focuses on describing the boundary of the object, including its surfaces, edges, and vertices, rather than the volume of the object itself.

STL

Stereolithography is a widely used file format for 3D printing and computer-aided design (CAD). It is primarily used for representing 3D models in a way that can be understood by 3D printers, CNC machines, and other manufacturing technologies.

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Frequently asked questions

Find answers about converting files with Marathon OS brep to stl converter.

  • How do I convert BREP to STL online?

    Upload your BREP file (.brp or .brep) to Marathon OS, choose STL as the output format, and download the converted file in seconds — no software installation required.

  • Why convert BREP to STL?

    Converting BREP to STL helps you move CAD data between tools, suppliers, and workflows without installing desktop software. Marathon OS handles the conversion in the cloud so you can download a STL file in seconds.

  • What BREP and STL file extensions are supported?

    This converter accepts .brp or .brep input files and outputs .stl. Upload up to 300 MB per file.

  • Is the BREP to STL converter free?

    Yes — converting BREP to STL on Marathon OS is completely free with no usage limits or hidden costs.

  • How is my data stored and secured?

    Your files are encrypted during upload, processed securely in the cloud, and automatically deleted after 24 hours.

  • Do I need any special software or training?

    No — upload your BREP file and download STL directly in your browser. No plugins or desktop CAD tools required.

  • Can I convert large BREP models to STL?

    Yes — Marathon OS is optimized for large and complex CAD models. You can upload files up to 300 MB for BREP to STL conversion.