Privacy Policy

Last updated: February 2026

        Short version: We do not collect, store, or transmit your diagram content. Everything you create stays in your browser. We use Google Analytics for anonymous usage statistics only.
    

1. Who We Are

This tool is operated by Ranjan Kumar as a free personal project. The service is available at mermaid.ranjankumar.in.

2. Information We Do Not Collect

We do not collect, store, or process:

Any diagram or Mermaid code you create or edit
Files saved through the File Manager
Your name, email address, or any personal identifiers
Account or login credentials (there is no account system)

All diagram content lives exclusively in your browser's localStorage and sessionStorage. It is never transmitted over the network.

3. Analytics

We use Google Analytics (GA4) with the measurement ID G-M0GCVQRDDS to understand aggregate usage patterns. This may collect:

Pages visited and time spent
Browser type and operating system
Approximate geographic region (country/city)
Referring website

This data is anonymised and aggregated. It is governed by Google's Privacy Policy. You can opt out using the Google Analytics Opt-out Browser Add-on or a content blocker such as uBlock Origin.

4. Cookies

The site itself sets no cookies. Google Analytics sets its own cookies (_ga, _gid) for session tracking. These are third-party cookies governed by Google's policy.

5. Local Storage

The application uses your browser's localStorage and sessionStorage to save your diagram state and named files. This data:

Never leaves your device
Can be cleared at any time by clearing your browser's site data
Is not accessible to us or any third party

6. Third-Party Libraries

The tool loads the Mermaid JavaScript library from cdn.jsdelivr.net. This CDN may log the request (your IP address and browser info) in its access logs, governed by jsDelivr's Privacy Policy. No diagram content is sent to jsDelivr.

7. Children's Privacy

This tool is not directed at children under 13. We do not knowingly collect information from anyone under 13. Because we collect no personal data at all, no special risk exists.

8. Changes to This Policy

We may update this policy as the service evolves. The "Last updated" date at the top of this page will reflect any changes. Continued use of the service after a policy update constitutes acceptance of the revised policy.

9. Contact

If you have questions about this Privacy Policy, please reach out via ranjankumar.in.