Mermaid Editor
Write Mermaid syntax and see a live flowchart, sequence, or class diagram preview. Export as SVG, PNG, or JPEG.
About Mermaid Flowchart Editor
Write Mermaid diagram syntax in the editor and see the rendered flowchart, sequence diagram, class diagram, or other chart types update instantly. Load a template to get started quickly, then export your diagram as SVG, PNG, or JPEG, or copy the syntax for later editing.
What Is This Tool?
A live Mermaid diagram editor that renders flowcharts, sequence diagrams, class diagrams, and more as you type. Write diagrams as text using Mermaid syntax and instantly see the rendered result, then export it as an image.
How to Use
- Pick a template (Flowchart, Sequence, Class, and more) to load example Mermaid syntax, or write your own.
- Watch the diagram preview update automatically as you edit the syntax.
- Click Export Image to download the diagram as SVG, PNG, or JPEG, or Copy Syntax to copy the Mermaid code.
- If the syntax has an error, the last valid diagram stays visible while you fix it.
Common Use Cases
- Sketching a flowchart for a process or decision tree
- Documenting an API call sequence or system interaction
- Drawing a class diagram or entity-relationship diagram for software design
- Embedding diagram-as-code in documentation or README files
Tips & Tricks
- Mermaid syntax is plain text, so diagrams can be version-controlled alongside your code.
- Use the SVG export for crisp diagrams in documentation, and PNG or JPEG for quick sharing in chat or slides.
Frequently Asked Questions
What types of diagrams does Mermaid syntax support?
Flowcharts, sequence diagrams, class diagrams, state diagrams, entity-relationship diagrams, and several other diagram types — pick a template to load example syntax for each.
What happens if I make a syntax error while editing?
The editor keeps showing the last valid diagram rendered so your work in progress stays visible, rather than clearing the preview — fix the syntax error and the diagram updates automatically.
Which export format should I choose: SVG, PNG, or JPEG?
SVG is vector-based and stays crisp at any zoom level, ideal for documentation. PNG and JPEG are raster formats better suited for quick sharing in chat apps or slide decks where SVG support may be limited.
Can I store my diagrams in version control alongside my code?
Yes. Since Mermaid diagrams are written as plain text syntax, you can commit the .mmd source directly to git and track changes to the diagram just like any other code file.
Is my diagram syntax sent to a server to render?
No. Diagrams are rendered entirely client-side in your browser — your syntax and diagram content are never uploaded anywhere.
Write Mermaid syntax and see a live flowchart, sequence, or class diagram preview. Export as SVG, PNG, or JPEG for free, no signup required.