Free tool
Security Headers Checker
Enter your app's URL to grade its HTTP security headers. We check the headers that protect against XSS, clickjacking and protocol-downgrade attacks, and show you exactly what's missing.
Missing headers?
Read how to add security headers, or get a full launch-readiness review with a signed clearance:
FAQ
- Which security headers matter most?
- Content-Security-Policy and Strict-Transport-Security carry the most weight — CSP is your main defense against cross-site scripting and HSTS forces HTTPS. X-Content-Type-Options and X-Frame-Options round out the baseline.
- Do AI-built apps usually have these?
- Rarely. Apps generated by AI builders almost always ship without security headers, which is why adding them is one of the quickest wins before launch.