Why check HTTP headers from a server instead of the browser?

Browser CORS policies block client JavaScript from reading response headers on external domains. Running the request through ToolCix's server route returns every response header cleanly.

Which security headers should production sites include?

At minimum, configure X-Content-Type-Options: nosniff, Referrer-Policy, X-Frame-Options or frame-ancestors CSP, and Strict-Transport-Security on HTTPS domains.

Does it follow redirects?

ToolCix captures redirect location details and final response status so you can spot 301 vs 302 vs 308 behavior.

Can I check localhost URLs?

No—private network IPs and loopback addresses are blocked for security.

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HTTP Header Checker

Essential for DevOps engineers, SEOs, and security teams verifying CDN caching, HSTS, CSP, and canonical redirects.

How to Use HTTP Header Checker

1Enter any public https:// URL you want to inspect.
2Click Inspect Headers to perform a live server-side HTTP request.
3Examine the response status code, round-trip latency, and full header table.
4Review automated security & caching header pass/warn badges.

Key Features

Full response header key-value inspection with copy button
Security audit for HSTS, CSP, X-Content-Type-Options, and X-Frame-Options
Cache-Control, ETag, and Content-Encoding diagnostics
SSRF-hardened server route with fair-use rate limiting

Why HTTP Headers Matter for Performance and Security

Response headers silently govern how browsers cache assets, enforce HTTPS, compress text payloads, and block clickjacking attacks. A misconfigured Cache-Control header can bypass your CDN completely, driving up origin latency and hurting TTFB.

ToolCix's HTTP Header Checker surfaces every raw response header alongside an actionable security and caching checklist so teams spot regressions right after deployment.

Verifying Trailing Slashes and Canonical Redirects

Search engines expect non-canonical variants (such as HTTP to HTTPS or missing trailing slashes) to issue clean permanent redirects rather than serving duplicate 200 responses. Inspect both variants here and verify page metadata with our Website SEO Analyzer.