npm Bundle Size Checker
UtilitiesMeasure the impact of adding an npm package to your project. See minified, gzipped, and Brotli size estimates before you run `npm install`.
Analyze npm footprint
Search for any package above to begin the audit.
Cost-Effective Dependency Management
Network Speed Impact
Calculate exactly how many seconds an extra package adds to your initial load on 3G and 4G networks.
Smart Alternatives
Find lighter alternatives for common heavy-hitters like `moment.js` and `lodash` before they bloat your output.
Dependency Analysis
The tool breaks down all sub-dependencies to show exactly which child package is contributing the most to the overall size.
npm Bundle Size Checker FAQs
We use the BundlePhobia API, which bundles each package using modern tools like Webpack and Rollup to provide accurate minified and compressed size estimates.
Minified size is the raw code after compression (removing whitespace, renaming variables). Gzipped size is the final compressed size that travels over the network; this is the most critical metric for performance.
Yes! Simply use the `package-name@version` syntax to check any relative version (e.g., `lodash@4.17.21`) or relative tags (e.g., `react@latest`).
Modern web performance is tied to JavaScript size. This checker helps developers find lightweight alternatives to heavy libraries, reducing initial load times for users.