HTTP Headers Checker + Security Headers Grade
See every HTTP response header of a URL and get an A–F security grade with copy-paste fixes for missing security headers.
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Runs entirely in your browser. Your files and text are never uploaded to our server.
- Instant results
- 100% free
- No sign-up
- Private
Enter a URL and click Check headers. You get a security grade from A+ to F, a list of missing security headers with copy-paste fixes, the redirect chain and every response header the server sent.
More about HTTP Headers Checker + Security Headers GradeHow to use, good to know & FAQ
Security headers we check
- Strict-Transport-Security (HSTS)
- Content-Security-Policy (CSP)
- X-Frame-Options
- X-Content-Type-Options
- Referrer-Policy
- Permissions-Policy
How to check HTTP headers
- Type a URL, e.g. https://example.com.
- Click Check headers.
- Add any missing headers in your server, CDN or plugin settings, then check again.
Frequently asked questions
What are HTTP security headers?
Response headers that tell browsers how to protect your visitors – forcing HTTPS, blocking clickjacking and limiting scripts.
How do I add security headers in WordPress?
Use your host or CDN settings (for example Cloudflare Transform Rules) or a security plugin, or add them in .htaccess on Apache.
Does a better grade improve SEO?
Not directly, but HTTPS and a secure, trustworthy site help users and rankings over time.
When to use it
After launching a site, during a security review, or when debugging caching, redirects or CORS.
Related: Check the certificate as well with the SSL Checker.