Mermaid is a JavaScript-based diagramming and charting tool that renders Markdown-inspired text definitions to create diagrams dynamically in the browser. It supports flowcharts, sequence diagrams, class diagrams, state diagrams, Gantt charts, pie charts, ER diagrams, and more.

Use graph TD (top-down) or graph LR (left-right) to define the layout. Nodes are defined with letters or identifiers, and edges connect them using arrows like -->. You can add labels, shapes, and styles. Check the examples dropdown for a quick start.

Yes! This online editor allows you to export your diagrams as SVG (vector) or PNG (raster) directly from your browser. Use the buttons above the editor to download.

Mermaid supports flowchart, sequence diagram, class diagram, state diagram, entity relationship diagram, user journey, Gantt chart, pie chart, requirement diagram, and more. Each uses a simple text syntax that's easy to learn.

No. All rendering happens locally in your browser using the Mermaid library. Your diagram code never leaves your device unless you explicitly share it.