CORS Checker
Check a URL for CORS headers and policies.
Results will appear here
Enter a URL and click "Check CORS" to simulate a request.
How this works
This tool makes a `fetch` request directly from YOUR browser to the target URL. It does not use a proxy. This is the only way to accurately test if a server's CORS policy will block a real frontend application. If the request fails, the most valuable information will be in your browser's developer console.
About the CORS Checker
A tool to diagnose Cross-Origin Resource Sharing (CORS) issues. This checker simulates a request from a browser to your API endpoint to see if it would be blocked by CORS policies, helping you debug and configure your server correctly.
CORS errors are a common frustration in web development. This tool helps you quickly determine if your server is sending the correct `Access-Control-Allow-Origin` headers. By simulating a cross-origin request, you can verify your server's configuration without writing complex test code, saving you significant debugging time.