Account and cloud save: signing in, the free limit, what gets stored

No account needed; sign-in only unlocks cloud save

Pasting, rendering, exporting and the auto-saved copy on this device never need an account, and never will. Sign-in only appears behind the editor's “Cloud” button (on phones: “Cloud save” in the “Download” panel). It exists to store diagrams on the server so you can open them elsewhere. Until you click it, the page sends no diagram content to the server.

How to sign in

• Email code: enter your address, receive a 6-digit code by email and type it in within 10 minutes. One email per address per 60 seconds, at most 10 a day; after 5 wrong attempts you need a new code.
• Google: click “Continue with Google”, pick an account on Google's page and you're sent back to the editor. A Google account and an email-code sign-in with the same address are the same Diagramate account.

You stay signed in on this browser for 30 days. “Sign out” only signs out the current device.

The free limit and what is stored

The free tier holds 20 diagrams. Each one stores the Mermaid code, the theme you had selected, the name you gave it, and the last 20 versions (each “Save new version” adds one). Exported PNG / SVG / PDF / Word / PowerPoint files are never uploaded; export always happens in your browser.

Deleting a diagram frees its slot immediately.

Saving, opening, other devices

• Save the current diagram to the cloud: the first save asks for a name; from then on the editor's top bar shows that name. When the content changes, a small dot appears meaning “changes not yet saved to the cloud”; open “Cloud” and click “Save new version”.
• Open: click a diagram in “My diagrams” and the editor's content and theme are replaced. If the current content isn't saved yet, you're asked whether to save first or open anyway.
• Save as new diagram: stores the current content as a separate diagram without touching the original.
• Another device: sign in with the same account and the same list is there.

When two devices both changed a diagram

If the cloud already has a newer version when you save (for example, you saved from another device), you'll see “There is a newer version in the cloud” with two choices:

• Overwrite: stores this device's content as the newest version. The previous version stays in the history; nothing is lost.
• Use the cloud version: drops this device's changes and loads the cloud version into the editor.

First sign-in: import this device's diagrams

The first time you sign in, if this browser has auto-saved diagrams (one for the editor, one for the mind map page), you're asked once whether to save them to the cloud. After importing, the diagram in the editor is linked to its cloud copy, so later saves add versions. “Not now” stops the prompt; you can always use “Save the current diagram to the cloud” by hand.

Privacy

• Not signed in: your diagram is never uploaded (the one exception is described in AI fix and AI tidy: clicking an AI button sends the code once, and it isn't stored).
• Signed in: only when you click save does that diagram's code, theme and name go to the server, and you can delete it from the list at any time.
• The server stores no plain-text codes; sign-in sessions are stored as hashes only.

Share links (/editor#pako:…) are unrelated to cloud save: what's in the link never passes through a server.