HTTP Security Headers Checker

HTTP security headers are directives sent by the server that instruct browsers how to handle content. Missing headers are one of the most common — and easiest to fix — web security vulnerabilities. Tools like securityheaders.com and ShipSafer check for their presence and correct configuration.

What it checks

  • Content-Security-Policy (CSP)
  • X-Frame-Options (clickjacking protection)
  • X-Content-Type-Options: nosniff
  • Referrer-Policy
  • Permissions-Policy
  • Strict-Transport-Security (HSTS)
  • Cross-Origin Resource Policy (CORP)

Why it matters

Missing security headers are responsible for a wide range of attacks: clickjacking, XSS, MIME-type sniffing, and information leakage. They take minutes to add and can prevent entire vulnerability classes.

Common issues found

No Content-Security-Policy headerMissing X-Frame-Options (clickjacking risk)No X-Content-Type-Options: nosniffOverly permissive CORS headersMissing Referrer-Policy

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Free, instant Security Headers check — no account required