JavaScript & TypeScript Complexity Checker
Measure cyclomatic complexity and maintainability on JS/TS snippets in the browser.
Paste a JavaScript or TypeScript module to see function-level cyclomatic complexity, line counts, and maintainability index. Uses AST analysis—not regex guessing.
Source is analyzed in-memory in your browser only.
Use cases
- Review a suspicious function before refactoring.
- Teach complexity metrics in code review training.
- Compare maintainability before and after a refactor.
Frequently asked questions
Which languages are supported?
JavaScript and TypeScript snippets. For C# cyclomatic complexity, use the Code complexity checker (C#) tool.
What cyclomatic complexity is too high?
Many teams flag functions above 10–15. Context matters—use this as a signal, not a hard gate.
Is this the same as CodeInspector scans?
No. This is a lightweight educational snippet tool. CodeInspector applies rule catalogs across whole repositories.
Related tools
Scale quality checks to entire repositories with CodeInspector scans.