What is cyclomatic complexity?

Cyclomatic complexity counts the number of independent paths through your code. Each if, else if, for, while, do-while, switch case, &&, and || adds 1. A score of 1–10 is considered simple and well-structured; 11–20 is moderate; above 20 is complex and hard to test.

Which programming languages are supported?

The analyzer is language-agnostic and uses pattern matching, so it works with most C-style languages (JavaScript, TypeScript, Java, C, C++, C#, Go, Swift), Python, Ruby, PHP, and more. Results may be approximate for highly dynamic or unusual syntax.

How is the maintainability score calculated?

The score uses a simplified version of the Maintainability Index: it starts at 100 and deducts points based on lines of code, cyclomatic complexity, and nesting depth. Scores above 70 are Good, 40–70 are Fair, and below 40 are Poor.

How can I reduce cyclomatic complexity?

Extract nested conditionals into well-named helper functions, replace chains of if/else with lookup tables or polymorphism, use early returns to flatten nesting, and break large functions into smaller single-responsibility ones.

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Code Complexity Analyzer

Measure lines of code, cyclomatic complexity, nesting depth, and maintainability

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このツールについて

Paste any code snippet and get instant, language-agnostic metrics: total lines, blank lines, comment lines, and code lines; cyclomatic complexity (count of decision points — if, else, for, while, switch, case, &&, ||); function count (function, def, func keywords); maximum nesting depth (by tracking indentation changes); and a maintainability score derived from LOC and complexity. Each metric comes with an interpretation badge (Good / Fair / Poor) so you can prioritise refactoring work. Practical tips for reducing complexity are shown inline whenever a metric exceeds the recommended threshold.

使い方

1 Paste your code snippet into the text area.
2 Click 'Analyze' — metrics appear instantly below the editor.
3 Check the colour-coded badges: green means Good, yellow is Fair, red is Poor.
4 Review the inline tips for any metric flagged as Fair or Poor.
5 Refactor your code and re-paste to see the updated scores.

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使い方

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