HTTP Header Checker
Lookup and audit standard HTTP request and response security headers (HSTS, CSP, X-Frame-Options).
How to Use HTTP Header Checker
Search for any HTTP header (e.g. Content-Security-Policy).
Read syntax definitions, recommended secure values, and security implications.
Copy production-ready header snippets.
Frequently Asked Questions
What does X-Frame-Options do?
It protects against clickjacking by preventing other domains from embedding your site inside an iframe.
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