📦 npm Dependency Analyzer

What Can the npm Dependency Analyzer Do?

The npm Dependency Analyzer is a free online tool that quickly analyzes dependency relationships in your package.json. It supports parsing dependencies, devDependencies, peerDependencies, and more, detecting version ranges, potential conflicts, duplicate dependencies, and visualizing dependency distribution with charts. All analysis runs locally in your browser — your package.json is never uploaded to any server.

Core Features

• Multi-type Dependency Parsing: Supports dependencies, devDependencies, peerDependencies, optionalDependencies, bundledDependencies
• Version Range Analysis: Parses ^, ~, >= and other semver range operators, highlighting exact vs. range versions
• Conflict Detection: Detects version conflicts for the same package across different dependency types and peer dependency mismatches
• Visual Distribution: Charts showing dependency type distribution ratios
• Report Export: Copy or download analysis reports

How to Use

1. Paste your package.json content into the input box, or drag and drop the file.

2. Select analysis options (version range analysis, conflict detection).

3. Click "Analyze Dependencies" to see results.

4. Review the dependency type distribution chart and detailed dependency list.

5. Copy or download the analysis report.

Use Cases

Case 1: Project Dependency Audit

When taking over a new project, quickly understand the full dependency landscape and identify core vs. dev dependencies.

Case 2: Version Upgrade Planning

Analyze current version ranges for major upgrades (e.g., React 17→18) and identify potential compatibility issues.

Case 3: Dependency Slimming

Find unused dependencies and replaceable heavy dependencies (lodash→es-toolkit) to optimize bundle size.

Case 4: Security Audit

Check if dependency version ranges are too broad (e.g., using * or latest) and narrow them to reduce supply chain attack risk.

Technical Background

npm semver version ranges use operators like ^ and ~: ^1.2.3 allows ≥1.2.3 and <2.0.0 (compatible minor updates), while ~1.2.3 allows ≥1.2.3 and <1.3.0 (patch updates only). Using * or latest installs any version, posing security risks. peerDependencies let plugins declare version requirements for host packages — npm v7+ auto-installs peer deps, with warnings on mismatches. Best practice: lock production dependencies to exact versions, use ranges for dev dependencies, and pair with package-lock.json for reproducible builds.