A LITTLE HELP FOR YOUR NEXT TASK
CORS Policy Tester
Simulate CORS decisions from supplied request and response settings.
Private by design
Your inputs stay on your device and are not sent to our servers. Optional usage analytics does not receive your files or tool inputs.
Preparing local security workspace…
How to use CORS Policy Tester
- Enter the requesting origin and request details.
- Paste the response and preflight headers.
- Inspect the matching rules and reasons for a simulated rejection.
What are the limits of CORS Policy Tester?
No network request. Models common Fetch CORS checks, not redirects, private-network access, browser caching or every Fetch edge case. CORS is not authentication. This tool processes inputs in browser memory and makes no upload or lookup request. Clear inputs or close the tab when finished. Exports and clipboard actions are explicit.