Mermaid Live Editor
Real-time Mermaid editor with instant preview while you type.
Waiting for a build step or refresh breaks the flow when you're iterating on diagrams. Utilitoo's Mermaid Live Editor renders your diagram on every keystroke so you can see syntax fixes and layout changes immediately without leaving the page.
Use it when tuning flowchart branches, adjusting sequence diagram participants, or experimenting with Gantt chart dates during a planning session. The split layout keeps code and preview visible at the same time on desktop, and stacks cleanly on mobile when you're reviewing on the go.
Export finished diagrams as SVG for documentation sites or PNG for slide decks. Copy the Mermaid source back into your README, wiki, or Markdown file with one click.
All rendering is client-side on Utilitoo. Nothing is sent to a server, which makes it safe for internal architecture drafts and product flows that aren't ready to share externally. Free, responsive, and built for anyone who wants live feedback while writing diagram code.
Live preview follows your site theme. Toggle light/dark mode from the header.
Diagram preview will appear here…
How to use
- Type Mermaid syntax in the editor panel.
- See the diagram update live in the preview panel.
- Copy or export the result when the layout looks right.
Frequently Asked Questions
How does live preview work in the Mermaid editor?▼
Utilitoo re-renders your diagram shortly after you stop typing, so the preview stays in sync with your latest Mermaid code without manual refresh.
Can I use the live editor for flowcharts and sequence diagrams?▼
Yes. Paste or write any supported Mermaid diagram type and the preview updates in real time as you edit.
Will live preview slow down my browser?▼
Utilitoo debounces rendering for smooth typing. Typical diagrams update instantly; very large diagrams may take slightly longer on older devices.
Can I download diagrams from the live editor?▼
Yes. Export SVG for scalable docs or PNG for presentations directly from the toolbar above the editor.
Is live rendering done on a remote server?▼
No. Utilitoo renders Mermaid locally in your browser, keeping your diagram content private.
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