- Home
- CDN Software
- UNPKG
UNPKG
What it is
UNPKG is a free web and API CDN for files published on npm. URLs identify a package, version, and file path, while version selection can use an exact release, an npm dist-tag, or a semver range. If no version is supplied, UNPKG uses the latest tag. Package resolution includes the exports specification, subpaths, and custom export conditions through a query parameter. Browser applications can load JavaScript modules with import maps without a bundler. The esm.unpkg.com service transforms TypeScript and JSX, bundles package internals, rewrites dependency imports to pinned UNPKG URLs, and serves modules for modern browsers. Module URLs expose options for targets, development mode, aliases, dependency overrides, JSX transforms, minification, source maps, metadata, and raw files. Adding ?meta returns JSON file metadata and subresource integrity values. UNPKG mirrors npm packages, runs on Cloudflare’s edge network and Workers, and says new npm files appear within minutes. It is open source and not affiliated with npm.
For and against
For
- Free web CDN and API access
- Supports npm versions and semver ranges
- Browser modules can use import maps
- Provides metadata and integrity values
- Runs across Cloudflare edge locations
Against
- Unresolved versions redirect to resolved URLs
- Latest-tag URLs may change over time
- Project is not supported by npm
The verdict
UNPKG offers URL-based access to npm files and browser module tooling without requiring a bundler. Developers needing stable caching should use full versions and file paths.
Who it suits
UNPKG suits developers serving npm files directly in websites or browser applications. It is also useful for small projects and prototypes that avoid a build pipeline.
Plans and prices
UNPKG
No plan or usage limits stated on the maker’s pages
Read 9 Oct 2026 · unpkg.com
On the record
- Browser apps
- UNPKG supports loading JavaScript modules directly in browser apps with import maps and without a build step.unpkg.com · read 9 Oct 2026
- Browser modules
- esm.unpkg.com transforms TypeScript and JSX when needed, bundles package internals, rewrites dependency imports to permanent URLs, and serves browser-loadable modules.unpkg.com · read 9 Oct 2026
- Caching
- UNPKG says it runs on Cloudflare’s global edge network and caches files by permanent URLs containing the npm package version.unpkg.com · read 9 Oct 2026
- Cloudflare infrastructure
- UNPKG says it runs on Cloudflare's global edge network and Cloudflare Workers, serving requests from hundreds of locations worldwide.unpkg.com · read 4 Oct 2026
- File resolution
- When a file path is omitted, UNPKG resolves the package’s default entry point, including support for package exports and subpaths.unpkg.com · read 9 Oct 2026
- Inline scripts
- The /run helper transforms inline TypeScript, JSX, and TSX scripts through esm.unpkg.com and inserts executable module scripts.unpkg.com · read 9 Oct 2026
- Integrity metadata
- The metadata example includes a SHA-256 subresource integrity value for each file.unpkg.com · read 4 Oct 2026
- Metadata
- Appending ?meta to a package root or subdirectory returns JSON file metadata, including paths, sizes, types, and subresource integrity values.unpkg.com · read 9 Oct 2026
- Metadata API
- Appending ?meta to a package root or subdirectory returns JSON metadata including file paths, sizes, types, and subresource integrity values.unpkg.com · read 4 Oct 2026
- Module options
- Browser module URLs support options including output target, development mode, custom conditions, dependency overrides, aliases, minification, and source maps.unpkg.com · read 9 Oct 2026
- No-build apps
- The site describes loading JavaScript modules directly into browser apps with import maps, without a bundler.unpkg.com · read 4 Oct 2026
- Nobuild use cases
- The maker describes UNPKG as suited to small projects, prototypes, and other browser apps that need to run without a build pipeline.unpkg.com · read 9 Oct 2026
- Notable cache behavior
- URLs using an unresolved version or range redirect to a resolved version, while the site recommends full version numbers and file paths for the best chance of a cache hit.unpkg.com · read 9 Oct 2026
- npm integration
- UNPKG mirrors npm packages, and the site says files become available on unpkg.com within minutes of publication to npm.unpkg.com · read 4 Oct 2026
- Package exports
- UNPKG supports the full package exports spec, including subpaths, and supports custom export conditions through a query parameter.unpkg.com · read 4 Oct 2026
- Package updates
- The site says npm files become available on UNPKG within minutes of publication.unpkg.com · read 9 Oct 2026
- Package versions
- Package URLs support exact versions, npm dist-tags, and semver ranges, and use the latest tag when no version is specified.unpkg.com · read 9 Oct 2026
- Project and affiliation
- UNPKG describes itself as an open source project from @mjackson and says it is not affiliated with or supported by npm.unpkg.com · read 9 Oct 2026
