Paste your code structure or describe a system and get a visual diagram instantly.
Code and diagrams are two sides of the same coin — code describes logic, diagrams communicate it. Mermaid Chart bridges both: describe a system in natural language, and AI generates the Mermaid syntax. Alternatively, write Mermaid code directly in the Monaco editor and see the diagram render in real time. The code is always the source of truth.
Every diagram is backed by Mermaid text — reviewable, diffable, versionable.
Describe the system and AI writes the Mermaid code.
Edit code, diagram updates. Edit diagram visually, code updates.
When code changes, update the diagram with a text diff — not a redraw.
Document a class hierarchy from a codebase, illustrate an API's request-response flow, visualize a state machine derived from code logic, or sketch a data model's entities and relationships.
Attach diagrams to pull requests to explain what changed architecturally. Reviewers see both the code diff and the visual representation.
Free plan includes the full editor — no credit card required.
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