Free tool
Security Headers Checker
Test HTTPS, HSTS, Content-Security-Policy, clickjacking protection, X-Content-Type-Options, Referrer-Policy, Permissions-Policy and server version disclosure — with a clear grade and explanation for each header.
How it works
Live checks. No sign-up.
- 01Enter a web address
- 02We request it and analyse the response headers
- 03Get a grade with an explanation for every header
Why do security headers matter?
Security headers tell browsers how to protect your visitors — for example by enforcing HTTPS, blocking clickjacking and limiting injected scripts. They are quick to add and close common attack paths.
Is an A grade enough to be secure?
No — headers are one layer. A full security review also covers the application, server configuration, dependencies, authentication and backups.
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