Free AI-powered Mermaid diagram generator. Describe your flow, database schema, or API in plain English — AI writes the Mermaid syntax, you get an editable diagram to export as SVG or PNG. No signup, no watermark.

Hey everyone 👋

Built this because I write a lot of design docs and always default to Mermaid — it's git-friendly and renders inline in GitHub/Notion/Obsidian. But every time I sit down to write one I lose a few minutes searching for the syntax. Seven diagram types, seven grammars.

So text2mermaid is exactly that: a text box that calls an LLM to write the Mermaid, with a live preview so you can see it work (or break) before pasting into your doc.

What I'd love feedback on:

Which diagram type do you use most? Right now I've tuned prompts for all seven, but flowchart and sequence get the most love — curious if class/state/ERD generation feels weaker to you.
How's the AI accuracy? The model occasionally produces valid-looking Mermaid that mermaid.js refuses to render. I show the error and let you edit the code, but I'm working on auto-retry with the error fed back into the prompt.
What's missing? Share links, dark mode for preview, VSCode plugin — all on the list, but I'd love to know what's #1 for you.

Free to use, no signup. The generated Mermaid code is yours — copy it out, drop it in git, done. No lock-in.

Grateful for any pushback! 🙏

Tried it with a quick API flow and it nailed the syntax on the first pass, even handling the conditional branches I half-expected to trip it up. The no-signup thing is genuinely nice when you just need a diagram in a hurry.

Tried it with a quick API flow description and the diagram came out clean and actually matched what I asked for. The no-signup, no-watermark part is a nice touch too.

being able to import an existing mermaid file and have the AI just clean it up or explain what it does would be super useful, since most of my diagrams already exist as messy code