Free HTTP Header Checker
Enter any URL to view its full HTTP response headers and a scorecard of the security headers that matter for SEO and safety — HSTS, CSP, X-Frame-Options, and more.
HTTP/2 200 OK content-type: text/html; charset=UTF-8 server: nginx strict-transport-security: max-age=31536000; includeSubDomains x-frame-options: SAMEORIGIN x-content-type-options: nosniff referrer-policy: strict-origin-when-cross-origin cache-control: max-age=3600, public
Why HTTP headers matter for SEO
Response headers control caching, security, and how content is served. Missing security headers (like HSTS or a Content-Security-Policy) won’t directly tank rankings, but HTTPS and a secure setup are trust signals — and headers like X-Robots-Tag and Cache-Control directly affect crawling and indexing.
Key security headers to set
- Strict-Transport-Security (HSTS) — forces HTTPS.
- Content-Security-Policy — mitigates XSS.
- X-Content-Type-Options: nosniff and X-Frame-Options.
Frequently asked questions
Is the HTTP header checker free to use?
Yes, it is completely free. Enter any public URL to instantly see its full HTTP response headers along with a security-header scorecard.
What security headers should my website have?
The most important are Strict-Transport-Security (HSTS), Content-Security-Policy, X-Frame-Options, X-Content-Type-Options, and Referrer-Policy. Together they help protect against attacks like clickjacking, MIME-type sniffing, and protocol downgrade.
How do I add missing security headers to my site?
Add them in your web server or application config — the Header directive in Apache, add_header in Nginx, or response middleware in your app. After deploying, recheck the URL to confirm the headers now appear in the response.
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