Logic Flowchart
Paste your code and generate a visual flowchart using Mermaid.js.
Click "Render" to generate flowchart
About Logic Flowchart
The Logic Flowchart tool converts source code into visual Mermaid.js flowcharts. Paste any function, method, or control-flow-heavy block and receive a rendered diagram that maps every conditional branch, loop, and function call to a visual node.
Understanding code logic through visual representation reveals patterns that are hard to spot in text alone. This tool parses the control flow graph — if statements, for and while loops, switch cases, try-catch blocks, and return statements — and renders each as a flowchart node with edges showing the possible execution paths.
Mermaid.js is the rendering engine, chosen for its wide platform support and markdown-friendly syntax. The generated diagram can be exported as an SVG or PNG image, or copied as Mermaid markup for embedding in documentation, Notion pages, GitHub README files, or any markdown editor that supports Mermaid blocks.
The tool supports most mainstream languages: JavaScript, TypeScript, Python, Java, Go, Rust, C#, and C++. For each language, the parser identifies branching constructs and translates them into uniform flowchart nodes. Complex paths like nested loops or recursion are annotated with subgraph boundaries to keep the diagram readable.
For extremely long functions, the tool provides a collapsing mechanism. You can choose to expand or collapse specific regions such as error-handling blocks, deeply nested loops, or initialization code. This keeps the high-level view clean while allowing drill-down into details.
Beyond debugging and documentation, these flowcharts are valuable for code review and knowledge transfer. Reviewers can visually trace the logic of a pull request without reading every line, and new team members can understand legacy code structure at a glance.
Frequently Asked Questions
Can I edit the generated flowchart?
Yes. The Mermaid source code is editable in the built-in editor. You can modify node labels, add annotations, or restructure the layout. Changes reflect in real time on the rendered diagram.
What export formats are available?
SVG, PNG, and raw Mermaid markdown. SVG is recommended for documentation because it scales cleanly and can be styled with CSS.
Does the tool handle recursive functions?
Yes. Recursive calls are visualized as a self-referencing edge or as a subgraph with a loop indicator. You can toggle between these representations in the settings panel.
How large of a code block can I paste?
The tool processes up to 500 lines of code per session. Functions longer than that trigger a warning and are truncated to the first 500 lines. You can process additional blocks in separate sessions.
Can I share the flowchart with my team?
Yes. You can generate a shareable link that preserves both the source code and the rendered diagram. The link is valid for 7 days and does not require authentication to view.