How to use the CDNJS API in C#

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

Online · 614 msEndpoint tested Oct 24, 2026

1. What you need

.NET 6 or newer. Paste into a top-level `Program.cs` and run `dotnet run`.

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

2. Make the request

using System.Net.Http;

using var http = new HttpClient { Timeout = TimeSpan.FromSeconds(10) };
var json = await http.GetStringAsync("https://api.cdnjs.com/libraries/jquery");
Console.WriteLine(json);

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.
Read the official documentation ↗ for rate limits and terms of use.

FAQ

Does the CDNJS API need an API key in C#?

No. The CDNJS API works without an API key, so the C# 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 · JavaScript · Node.js · PHP · Java · Go · Ruby
CDNJS API: ratings & reviews · CDNJS API alternatives · more free APIs for C#