CORS Tester

Use this little website to test if a URL is setup correctly to work with CORS.




If your CORS setup is not using a wildcard then this should be a domain that matches your AllowedOrigins


Shareable link:

Results

This URL will not work correctly with CORS.

What's wrong?

It does not have the access-control-allow-origin header set to *. Without this header, requests from other domains cannot be made to it via a users browser.

How to fix it?

If you have access to the server for the URL, you'll need to modify it to add the access-control-allow-origin header. If you do not have access, you'll need to upload the file somewhere else.

Headers

These are the response headers received when making the request.

cache-control: private, max-age=0, no-store, no-cache, must-revalidate, post-check=0, pre-check=0
content-length: 15
content-type: text/plain; charset=UTF-8
date: Thu, 05 Mar 2026 12:31:27 GMT
expires: Thu, 01 Jan 1970 00:00:01 GMT
referrer-policy: same-origin
server: cloudflare
x-frame-options: SAMEORIGIN

CORS tester was built by @mscccc. The code is available on GitHub. Sponsored by HTML/CSS to Image.