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cdnjs

cdnjs.com

Free plan WebAPI
Visit cdnjs.com
Spec score 7.8 #19 of 33 in CDN Software

What it is

cdnjs is a free web and API service for adding JavaScript, CSS and font resources to web projects. Libraries can be referenced with script or link tags, so projects do not need a build step or npm installation. Files are delivered through Cloudflare’s global network, which cdnjs lists as having more than 330 edge locations. HTTP/3, HTTP/2 and QUIC are supported, along with Brotli and GZIP compression. cdnjs is HSTS preloaded and supplies Subresource Integrity hashes for script and link tags. Its community-curated catalog lists 4,616 libraries. After approval, automation checks npm or GitHub for new versions and manages minification, compression, hash generation and publishing. The service does not pull arbitrary libraries on demand. An unauthenticated API is available at https://api.cdnjs.com. The listed cdnjs plan costs nothing.

Spec sheet

What it does
cdnjs serves JavaScript, CSS, and font resources for use in web projects.Read 9 Oct 2026 · cdnjs.com
Free plan
YesRead 24 Sep 2026 · cdnjs.com
API
The API base URL is https://api.cdnjs.com and the site says no authentication is required.Read 9 Oct 2026 · cdnjs.com
Security
cdnjs is HSTS preloaded and provides Subresource Integrity hashes for script and link tags.Read 9 Oct 2026 · cdnjs.com
Support
Users can contribute through GitHub and support maintenance through GitHub Sponsors, Open Collective, or Patreon.Read 9 Oct 2026 · cdnjs.com
Founded
2011Read 28 Sep 2026 · cdnjs.com
Curation limit
cdnjs serves libraries added by the community and does not provide on-demand pull-through access to arbitrary libraries.Read 9 Oct 2026 · cdnjs.com
Global delivery
Files are served from Cloudflare's global network, which the site lists as having 330+ edge locations.Read 9 Oct 2026 · cdnjs.com
How to include assets
Libraries can be included with a script or link tag, without a build step or npm install.Read 9 Oct 2026 · cdnjs.com
Integrations and sponsors
The site credits Cloudflare for CDN infrastructure and project maintenance, Algolia for library search, DigitalOcean for infrastructure, and Statuspage, Sentry, and UptimeRobot for incident communication, error monitoring, and uptime monitoring.Read 9 Oct 2026 · cdnjs.com
Library catalog
The browse page lists 4,616 available libraries.Read 9 Oct 2026 · cdnjs.com
Library updates
After a library is approved and added, automation regularly checks npm or GitHub for new versions and handles minification, compression, SRI hash generation, and publishing.Read 9 Oct 2026 · cdnjs.com
Protocols and compression
The service supports HTTP/3, HTTP/2, QUIC, Brotli, and GZIP compression.Read 9 Oct 2026 · cdnjs.com
Scale
The site reports 12.5% of websites and 250 billion requests per month.Read 9 Oct 2026 · cdnjs.com

Plans and prices

cdnjs Free Free to use Curated libraries added by the community Read 9 Oct 2026 · cdnjs.com

Every cdnjs plan and price →

Strong points and limits

Strong points

  • Free plan costs 0.00 USD
  • Script and link tag inclusion
  • HTTP/3, HTTP/2 and QUIC support
  • Subresource Integrity hashes provided
  • Unauthenticated API available

Limits

  • Only community-curated libraries are available
  • No on-demand arbitrary library pull-through
  • Catalog limited to 4,616 libraries

Who it suits

cdnjs suits web developers who want hosted library assets without installing packages or running a build step. It is also useful for projects needing a public API and integrity hashes.

Verdict

cdnjs provides a free, tag-based way to consume a defined catalog of web libraries. Its curation model means an unlisted library cannot be fetched on demand.

Where Specifiction places it

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