Mermaid Diagram
Render Mermaid diagrams from text: flowcharts, sequence diagrams, ER charts, and more. Paste DSL, preview the graph, and copy the source for docs. Rendering is client-side so architecture sketches do not leave your machine.
Runs in your browser. Nothing is uploaded.
About this tool
Render Mermaid flowcharts, sequence diagrams, and other DSL in the browser. The mermaid library is lazy-loaded with next/dynamic and ssr: false, then diagrams re-render on a short debounce as you type. A loading state appears until the library is ready.
How to use: start from a flowchart or sequence template, edit the source, wait for the SVG preview. Copy the source for docs. Invalid DSL shows an error instead of a blank canvas.
Example: a three-node flowchart is enough for a README architecture sketch. Sequence diagrams help API call order. This is not a full diagram SaaS with collaboration or export to every vendor format.
Architecture sketches are not uploaded to a diagram host. Rendering uses client-side mermaid only. After the library loads once, you can keep editing offline. Keep diagrams short for readability; huge graphs may be slow in the tab. Copy source into a README rather than screenshotting if you can.
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