How to use the CDNJS API in JavaScript

Library info on CDNJS. A free development API by cdnjs.com. This guide calls it from JavaScript with code we've run against the live endpoint.

Online · 614 msEndpoint tested Oct 24, 2026

1. What you need

Any modern browser. Paste the code into the DevTools console or a module script tag.

No API key or sign-up. Endpoint: https://api.cdnjs.com/libraries/jquery

2. Make the request

JavaScript

const res = await fetch("https://api.cdnjs.com/libraries/jquery");
if (!res.ok) throw new Error(`HTTP ${res.status}`);
const data = await res.json();
console.log(data);

3. The response

Trimmed from the live response on Oct 24, 2026.

JSON

{
  "name": "jquery",
  "latest": "https://cdnjs.cloudflare.com/ajax/libs/jquery/4.0.0/jquery.min.js",
  "sri": "sha512-8LENNbXmzI/Gbj+OwXmqR6V4QaUAw0/porPzy1+dQoJqC0JPHedWoe0DDOTL2uHA5XXJyI...",
  "description": "JavaScript library for DOM operations",
  "keywords": [
    "jquery",
    "library",
    "ajax"
  ],
  "version": "4.0.0",
  "filename": "jquery.min.js",
  "homepage": "https://jquery.com/",
  "license": "MIT",
  "repository": {
    "type": "git",
    "url": "https://github.com/jquery/jquery.git"
  },
  "autoupdate": {
    "source": "npm",
    "target": "jquery"
  },
  "versions": [
    "4.0.0",
    "4.0.0-rc.2",
    "4.0.0-rc.1"
  ]
}

4. Before you ship

Set a timeout and handle non-200 responses: free APIs can rate-limit or go down.
Cache responses where you can, instead of calling the API on every page view.
Browser calls depend on CORS. If a request is blocked, move it to a server or serverless function.
Read the official documentation ↗ for rate limits and terms of use.

FAQ

Does the CDNJS API need an API key in JavaScript?

No. The CDNJS API works without an API key, so the JavaScript example runs as-is.

Can I call the CDNJS API from the browser?

Yes. It sends CORS headers, so front-end JavaScript can call it directly.

What does the CDNJS API return?

JSON. The example response on this page is trimmed from a real response our health check received on Oct 24, 2026.

Same API in: Python · Node.js · PHP · Java · Go · Ruby · C#
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