Source processing and website requests are different
Mermaid rendering, Markdown and JSON formatting, table generation, and batch export run in your browser. Pasted source and files you import are not uploaded to a conversion service. Downloads are assembled on your device.
Vercel hosts this website and receives normal HTTP requests and associated hosting logs when you load pages and static assets. Local source processing is not a claim that the host receives no data. This page does not promise a hosting-log retention period.
Fonts and application assets are served from this website, rather than an external font service. Markdown preview omits images and removes fetch-capable embedded content. Mermaid rendering rejects external resources and image labels; batch export extracts diagram code rather than fetching images from your document.
Optional drafts on this device
Draft saving is off by default. Enabling Remember my work on this device stores source and tool settings in this browser's localStorage. The preference applies across the tools and can restore saved work on later visits. This is not a cloud account or a backup service.
Clear saved data, available in the tool controls, turns saving off and removes the site's saved tool drafts and preference. Turning the remember option off does the same. The keys are mermaid-studio:remember and keys beginning with mermaid-studio:draft:; unrelated storage keys are not cleared.
Clearing saved data does not erase downloaded files, clipboard contents, browser history, or copies of share links. If the browser blocks storage access, the tool displays an error; clearing is not reported as successful when it fails. Avoid saved drafts for sensitive work on a shared browser profile.
Clipboard and files
Clipboard writes happen when you explicitly select a copy action, such as Copy JSON, Copy formatted, Copy PNG, or copying a share link. The application does not automatically read your clipboard. Pasting into an editor is your action, not background clipboard access.
Your browser and operating system control clipboard permissions and may keep clipboard history or synchronize it elsewhere. Imported files are read locally after you select them. Downloaded files and printed or saved PDFs remain subject to your device's storage and sharing settings.
Share links are unlisted, not confidential
A diagram share link contains compressed source, theme, and filename in the URL fragment: the part after #. That fragment is not sent in the HTTP request for the page, but anyone with the full link can decode it and recover the readable source.
Compression is not encryption. These links have no password, expiration, or revocation control. They can remain in browser history, synchronized tabs, messages, or copied documents. Clearing a draft does not disable a link someone already has.
Do not put secrets in a share link. The tool rejects links longer than 12,000 characters; downloading source and sharing it through a channel you trust is an alternative, not an automatic privacy guarantee.
Cookies, analytics, and external pages
The application does not set cookies or include analytics tracking. Optional draft storage is localStorage, not a cookie. This describes the application, not a blanket promise about Vercel hosting or third-party services.
The Buy Me a Coffee support page and owner's public GitHub profile are ordinary links, not embedded widgets. Those services are contacted only if you follow the links, and their own privacy practices apply there.
Read About Mermaid Studio for ownership and support information. A public profile is not a private channel for source files or sensitive feedback.