HTTP Header Checker

What does an HTTP header checker do?

An HTTP header checker retrieves a URL and displays the response headers returned by the web server. HTTP headers provide information about how a server handled a request and how browsers, crawlers, caches and other clients should process the response. Reviewing these values can help with redirect troubleshooting, caching, content delivery, indexing directives, security controls and other technical website issues.

Why check HTTP response headers?

Important website instructions are not always visible in the HTML source. A response can contain a Location header that sends visitors to another URL, an X-Robots-Tag header that controls indexing, or a Cache-Control header that influences caching behavior. An HTTP header check makes these server-level details easier to inspect without relying only on the page source. For redirect-specific analysis, use the Redirect Checker to follow the complete request path.

Useful headers for technical SEO

Several response headers are especially useful when diagnosing technical SEO issues. Location helps identify redirect destinations, while the HTTP status code shows whether a request succeeded, redirected, or returned an error. X-Robots-Tag can communicate directives such as noindex through HTTP headers. You can compare those server-level directives with HTML markup using the Meta Noindex Checker. Content-Type confirms the type of resource returned, and Vary, Cache-Control, ETag and Last-Modified provide useful information about caching and content delivery.

Security and server response headers

HTTP headers can also reveal important security configuration. Headers such as Strict-Transport-Security, Content-Security-Policy, X-Content-Type-Options, Referrer-Policy and Permissions-Policy can help website owners understand how browsers are instructed to handle content and security-related behavior. The Server header, when provided, can identify the server software reported in the response.

How HTTP headers help troubleshoot a URL

When a page behaves differently in a browser, search crawler or caching layer, response headers can provide useful clues. For example, a redirect may be caused by a 301 or 302 response with a Location value, while an unexpected indexing directive may come from an X-Robots-Tag header. Comparing the status code and headers with the HTML source can help separate server-side configuration from page-level markup. The HTTP Status Codes guide can help interpret the response code.

What this checker can reveal

The results can help you confirm whether a URL returns the expected status, whether a redirect destination is supplied, and whether important SEO, caching or security headers are present. You can also compare the response from different URLs when investigating redirect chains, inconsistent caching, unexpected content types or server configuration changes. When crawler access is the question, the Robots.txt CheckerSitemap Checker provides a separate view of robots.txt rules.

Check HTTP headers online

Enter a public HTTP or HTTPS URL above to inspect its response. RedirectionChecker validates the destination before making the request and presents the returned status, response timing, resolved IP information and headers in clearly separated sections. Headers that are not included in the response are shown as Not present, so you can distinguish a missing header from a value that was actually returned.