WEB

HTTP Header Checker

Check HTTP headers

Input

Inspect the response headers of any website. Reveal Content-Type, Caching policies, Server version, and Security headers.

Terminal

Console ready. Execute a command to see output...

About HTTP Header Checker

The Hidden Conversation

Before a browser renders a page, the server sends a set of "Headers" defining the rules of engagement.

Important Headers to Watch

  • Status Code: 200 (OK), 301 (Redirect), 404 (Not Found), 500 (Error).
  • Cache-Control: Tells the browser how long to keep the file.
  • Content-Security-Policy (CSP): The modern firewall against XSS attacks.
  • Strict-Transport-Security (HSTS): Forces HTTPS connections.

How to use HTTP Header Checker

  1. Enter a URL
    Full URL (https://example.com/path) or just the host (https:// is the default if you skip the scheme).
  2. Hit Check Headers
    A HEAD request goes out from the packet.guru server with SSRF protection on every hop.
  3. Read the response
    Status code, statusText, the final URL after redirects, and every response header (one per line).
  4. Follow up
    Use SSL Checker on the same host for TLS details, or DNS Lookup for the underlying DNS record.

Frequently Asked Questions

A HEAD request to the URL you give it and the response headers the server sends back. You get the final status code, the resolved URL after redirects, and every header the server returns: Content-Type, caching policy (Cache-Control, Expires), security headers (Strict-Transport-Security, Content-Security-Policy, X-Frame-Options), Server identification, and so on.