Free Tool
Free HTTP Header Checker
Inspect HTTP response headers, status codes, redirects, and security headers for any URL. Debug caching, canonical, X-Robots-Tag, and other SEO-critical headers.
Why HTTP Headers Matter for SEO
HTTP response headers contain instructions that tell browsers and search engines how to handle your page. Headers control caching, redirects, security policies, and indexing directives. Misconfigured headers can prevent indexing, cause security issues, or slow down your site.
- Status codes — 200, 301, 302, 404, 500 indicate page health
- X-Robots-Tag — Can noindex pages at server level
- Cache-Control — Controls browser and CDN caching
- Content-Type — Must be correct for Google to parse the page
- Security headers — HSTS, CSP, X-Frame-Options protect your site
Common Header Issues to Watch For
These are the most common HTTP header problems that affect SEO and security:
- Redirect chains (301 → 301 → 200) waste crawl budget
- Missing HSTS header leaves HTTPS vulnerable to downgrade attacks
- No Cache-Control means browsers re-download assets every visit
- X-Robots-Tag: noindex accidentally blocking pages from Google
For a complete SEO analysis beyond headers, try the free SEO audit or check your SSL certificate.
FAQ
Frequently Asked Questions
200 (OK) means the page loads correctly. 301 (Permanent Redirect) means the page has moved — good for SEO. 302 (Temporary Redirect) should be used sparingly. 404 (Not Found) means a broken page. 500 (Server Error) indicates a server-side problem. 403 (Forbidden) means access is blocked.
The most important security headers are: Strict-Transport-Security (HSTS) to enforce HTTPS, X-Content-Type-Options to prevent MIME sniffing, X-Frame-Options to prevent clickjacking, and Content-Security-Policy (CSP) to prevent XSS attacks. These also signal to Google that your site takes security seriously.
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