3D tool

STL to OFF Converter

Convert an STL 3D model to OFF (Object File Format) for research, MeshLab and CGAL workflows.

STL OFF
PrivConvert
Privacy-first conversion
No files stored
In-memory processing
Deleted instantly
No sign-up needed

Complete the security check to begin

About Converting STL to OFF

STL is the universal 3D-printing format. It describes a model as a raw triangle mesh — just the surface geometry, with no colour, texture or units. Nearly every slicer and 3D printer accepts it, which is why it is the default export from most CAD tools for printing. When you need to move away from STL, the usual reason is simple: no colour, texture or material data.

Converting your STL 3D model to OFF solves that. OFF (Object File Format) is a simple, plain-text mesh format that lists a model’s vertices and faces. It is widely used in academia, geometry-processing research and tools such as MeshLab and CGAL, where a minimal, easy-to-parse mesh format is preferred. In practice you gain human-readable plain text and trivial to parse and generate. PrivConvert runs the whole STL-to-OFF conversion in server memory and deletes your file the instant the OFF is ready — nothing is stored, logged or reused.

When this conversion helps

  • You need human-readable plain text
  • You need trivial to parse and generate
  • You need standard in research and geometry-processing tools
  • Sharing a STL 3D model with someone whose software expects OFF

Tips for best results

  • Files up to 250 MB are supported, and you can batch-convert several STL files at once; each is processed privately and deleted immediately.

How to Convert STL to OFF Online

Converting STL files to OFF format is simple with PrivConvert. Our free online converter handles the entire process in your browser with no software installation required. Your files are processed securely in memory and never stored on our servers.

1
Upload your STL file

Drag and drop your file into the upload area, click to browse your device, or paste a URL to a file hosted online. You can upload files up to 250 MB and batch convert up to 20 files at once.

2
Automatic conversion

Once uploaded, the conversion from STL to OFF starts automatically. The process runs entirely in an isolated environment - your data never leaves the secure pipeline.

3
Download your OFF file

Your converted file is ready instantly. Click the download button to save it to your device. The file is deleted from memory immediately after download.

Why Choose PrivConvert?

Unlike other online converters that upload your files to remote servers, store them for days, and may use them for AI training or sell your data, PrivConvert was built with privacy as the foundation. Here's what makes us different:

Zero data retention

Files are processed in volatile memory (RAM) and immediately purged. Nothing is ever written to disk or backed up.

Encrypted transfers

All uploads and downloads are encrypted with TLS 1.3. Your files cannot be intercepted in transit.

No account required

Use any tool instantly without signing up, providing an email, or creating a profile. No tracking cookies, no user profiling.

Works on any device

Compatible with Windows, macOS, Linux, iOS, and Android. No plugins or desktop software needed - just a modern web browser.

STL vs OFF - Format Comparison

FeatureSTLOFF
File extension.stl.off
Full nameStereolithographyObject File Format
Introduced19871990s
EncodingBinaryText
EditableNoNo
Open standardYesYes
Supported by PrivConvertYes (as input)Yes (as output)
Privacy-safe conversionIn-memory, zero storage
Max file size250 MB per file
Batch supportUp to 20 files simultaneously

Trusted by Thousands of Users

PrivConvert processes thousands of file conversions every day. Our commitment to privacy and security has made us the go-to choice for professionals, developers, and privacy-conscious users worldwide.

250 MB Max file size
200+ Conversion tools
0 sec File retention
100% Free to use

Frequently Asked Questions

How do I convert STL to OFF?
Upload your STL file above and complete the quick security check. The mesh is parsed and rewritten as an OFF file in seconds, then offered for download. No software or sign-up needed.
Why convert STL to OFF?
OFF (Object File Format) is the format expected by many academic tools, CGAL and MeshLab. Converting from STL lets you feed a printable mesh into those research pipelines.
Is the geometry preserved?
Yes. Every vertex and triangle is carried over unchanged - only the file encoding changes. Both formats store plain surface geometry.
Is it private?
Every conversion runs in an isolated, network-free sandbox entirely in memory. Your file is never written to disk and is deleted the moment your download is ready.