Mermaid Diagram Studio
Flowcharts, sequence diagrams, class diagrams and Gantt charts: local parsing, strict security filtering, and exportable SVG / PNG plans.Processed locally (works offline)
Operations
Flowchart
Parse flowchart / graph nodes, edges and direction into a recognizable SVG plan with node groups and arrowed edges.
Sequence diagram
Parse sequenceDiagram participant / actor declarations, message arrows, notes and loop/alt blocks into participant lanes and message structures.
Class diagram
Parse classDiagram classes, members, direction and inheritance/composition/association relations into class boxes and relation lines.
Gantt chart
Parse gantt title, dateFormat, section and tasks (status/id/start/duration) into section headers and task bars.
Real examples and limits
Default budget: 100KiB of source and 1000 nodes; an 8-second render timeout can be cancelled or reset. Strict security mode rejects click / script / external links / %%{init} directives, never evaluates user code, and never writes source text into the export plan. This run implements deterministic type detection, validation, security filtering and export planning: the real Mermaid renderer and PNG rasterization are neither bundled nor tested. Parsing and SVG export work offline; no external renderer such as mermaid.ink or Kroki is contacted.
FAQ
Is my source uploaded?
No. Parsing, validation, security filtering and export planning happen locally in the browser and a module Worker. Source text is not persisted by default and the export plan records zero network requests.
Why is the result an exportable SVG plan instead of a real Mermaid diagram?
This run has no browser binary and does not bundle the Mermaid renderer. The deliverable is a recognizable, escaped, script-free deterministic SVG structure plus an export plan with a PNG non-blank-canvas policy. Real rendering and PNG rasterization are explicitly listed as untested in HANDOFF.
Are my inputs kept when a syntax error occurs?
Yes. Errors are localized as line N, column M (node X) and shown in the result area; the input is never cleared. Cancellation and timeouts also keep the source so you can reset and rerun.
Why are related tools not clickable?
mind, draw and dev are configuration placeholders. Per AL-PLAN, planned sites must not produce broken links; the build downgrades those anchors to plain text while keeping the site names.