About your data

Privacy and local data

The editor renders diagrams in your browser. Here is what stays local, and what uses a network connection.

Diagrams and saved projects

Mermaid source is processed in the browser. The editor stores workspace settings, projects, presets, and version history in localStorage for this site and browser profile. There is no application account or cloud project sync. Clearing site data removes those saved items. Export a JSON backup before clearing storage.

Shared links

Share links encode diagram content and settings in the URL fragment. Anyone who receives the link can open the diagram. Treat a shared link as a copy of its contents. URL fragments are not sent as part of normal HTTP requests, but scripts running on the page can read the page URL.

Network requests

The site host receives requests for pages and assets. The editor downloads Mermaid and supporting libraries from jsDelivr. Those providers receive ordinary request information, such as your IP address and browser request headers. An internet connection is needed to load dependencies that are not already cached.

Analytics

The page includes Google Analytics to measure site usage. Analytics may process page-view, browser, device, and interaction information and use cookies, depending on browser settings and service configuration. See Google’s privacy policy for its handling of that information. Do not place confidential information in page URLs.

Downloads and clipboard

Exports are generated in your browser and saved through its download mechanism. Copy actions write the selected output to your clipboard. Files and copied content are then managed by your device and any application where you paste or open them.

Your controls

Use browser site settings to remove stored data or manage cookies. Keep MMD source or JSON project backups if you need to move your work to another browser. File → Reset workspace clears the editor’s local saved data after confirmation.