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.

alt-svc: h3=":443"; ma=2592000,h3-29=":443"; ma=2592000
cf-cache-status: DYNAMIC
cf-ray: 9bc7dac8e76886d2-ORD
connection: keep-alive
content-type: text/html; charset=UTF-8
date: Sun, 11 Jan 2026 22:29:44 GMT
server: cloudflare
transfer-encoding: chunked

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