
jscpd
Find duplicate code blocks and analyze duplication metrics across files. Use when identifying copy-pasted code, measuring technical debt, or preparing for refactoring.
Find duplicate code blocks and analyze duplication metrics across files. Use when identifying copy-pasted code, measuring technical debt, or preparing for refactoring.
jscpd
Duplicate code detector supporting 150+ languages.
Usage
# Analyze directory
npx jscpd /path/to/source
# With pattern filter
npx jscpd --pattern "src/**/*.js" .
# Ignore directories
npx jscpd --ignore "**/node_modules/**,**/dist/**" .
# Minimum tokens to match (default: 50)
npx jscpd --min-tokens 30 .
# Output formats
npx jscpd --reporters json --output report.json .
npx jscpd --reporters html --output ./report/ .
Common Options
| Option | Description |
|---|---|
--min-tokens N |
Minimum tokens for duplicate detection |
--min-lines N |
Minimum lines for duplicate detection |
--threshold N |
Fail if duplication % exceeds threshold |
--ignore "glob" |
Ignore patterns (comma-separated) |
--reporters type |
Output format: console, json, html |
--output path |
Output directory for reports |
--silent |
Suppress console output |
Workflow
- Run jscpd to find duplicates
- Review the reported duplicates
- Refactor to eliminate duplication
- Re-run to verify cleanup
You Might Also Like
Related Skills

fix
Use when you have lint errors, formatting issues, or before committing code to ensure it passes CI.
facebook
frontend-testing
Generate Vitest + React Testing Library tests for Dify frontend components, hooks, and utilities. Triggers on testing, spec files, coverage, Vitest, RTL, unit tests, integration tests, or write/review test requests.
langgenius
frontend-code-review
Trigger when the user requests a review of frontend files (e.g., `.tsx`, `.ts`, `.js`). Support both pending-change reviews and focused file reviews while applying the checklist rules.
langgenius
code-reviewer
Use this skill to review code. It supports both local changes (staged or working tree) and remote Pull Requests (by ID or URL). It focuses on correctness, maintainability, and adherence to project standards.
google-gemini
session-logs
Search and analyze your own session logs (older/parent conversations) using jq.
moltbot
