Privacy Policy
Last updated: March 23, 2026
This Privacy Policy describes how MDSpin (“we”, “our”, or “us”) handles information when you use the MDSpin website and the MDSpin Chrome Extension (collectively, “the Service”). We are committed to protecting your privacy and being transparent about our data practices.
What MDSpin Does
MDSpin converts document files (PDF, DOCX, PPTX, TXT, HTML, RTF, CSV) into clean Markdown format. The Chrome Extension integrates directly into ChatGPT, Claude, and Gemini, allowing you to convert files to Markdown before sending them to the AI — improving context quality and reducing token costs.
Data We Process
File Contents
When you click the MDSpin convert button, the file you uploaded is read from your browser, encoded, and sent to our conversion API for processing. The file is converted to Markdown and the result is returned to your browser. We do not permanently store the contents of your files on our servers. Files are processed in-memory for the sole purpose of conversion and are not retained after the response is sent.
Authentication Data
If you sign in to MDSpin, we use Supabase as our authentication provider. This may include your email address and a session token. This data is used solely to manage your account and is governed by Supabase's Privacy Policy.
Local Preferences
The Chrome Extension stores a small amount of data locally in your browser (using Chrome's storage API) to remember your settings, such as whether inline buttons are enabled. This data never leaves your device.
Data We Do NOT Collect
- We do not track your browsing history
- We do not collect analytics or telemetry from the Chrome Extension
- We do not read or access the content of your conversations on ChatGPT, Claude, or Gemini
- We do not sell, rent, or share any personal data with third parties for advertising purposes
- We do not use cookies or tracking pixels in the Chrome Extension
Third-Party Services
The Service communicates with the following third-party services:
| Service | Purpose | Data Sent |
|---|---|---|
| MDSpin Conversion API | File-to-Markdown conversion | File contents (temporarily), filename, file type |
| Supabase | User authentication | Email address, session tokens |
We do not share your data with any other third parties.
Browser Permissions (Chrome Extension)
The Chrome Extension requests the following permissions, each for a specific purpose:
To detect when you are on a supported site (ChatGPT, Claude, or Gemini) and interact with the current tab
To save your preferences (e.g., inline button toggle) locally on your device
To copy converted Markdown to your clipboard as a fallback when direct file injection is not possible
To inject the MDSpin conversion button into supported chat interfaces
To authenticate your MDSpin account
Access to ChatGPT, Claude, and Gemini domains is required to display the conversion button and inject converted files within these specific sites
Data Security
All communication between the Extension and our servers is encrypted using HTTPS/TLS. File data is transmitted securely and processed in-memory without permanent storage. Authentication is handled through Supabase's secure infrastructure.
Data Retention
- File contents: Not retained. Files are processed in real-time and discarded immediately after conversion.
- Account data: Retained as long as your account is active. You may request account deletion at any time.
- Local preferences: Stored on your device only. Cleared when you uninstall the Extension.
Your Rights
You may:
- Uninstall the Extension at any time to stop all data processing
- Request deletion of your account and associated data
- Contact us with any privacy questions or concerns
Changes to This Policy
We may update this Privacy Policy from time to time. We will notify users of significant changes by updating the “Last updated” date at the top of this page.
Contact
If you have questions about this Privacy Policy, please contact us at: trenkner.peter@gmail.com