CORS Policy Tester
Work out why a CORS request is blocked and which response header the server is missing.
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Privacy & Security
Headers analyzed locally.
About This Tool
This tool runs entirely in your browser. No data is sent to any server, ensuring complete privacy. Simply use the interface above to get started — no registration or login required.
Disclaimer: This tool is provided "as is" without warranty of any kind. Results are for educational and utility purposes.
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