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Website & Performance

HTTP Response Headers Viewer

View every HTTP response header a URL returns — status code, HTTP version, full redirect chain, and notes on caching, compression, and security headers. Free.

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💡 What this shows

  • The full list of HTTP response headers a server returns for a URL.
  • The status code, HTTP version, and any redirect chain along the way.
  • Plain-English notes on common headers like Cache-Control, Content-Type, and HSTS.

Free HTTP Response Headers Viewer

See every HTTP response header a URL returns. Enter an address to view the status code, HTTP version, full redirect chain, and all response headers — with plain-English notes on common ones like Cache-Control, Content-Type, and HSTS. Free, no sign-up.

What are HTTP response headers?

Every time a browser requests a page or asset, the server replies with a set of HTTP response headers before the content itself. These headers carry crucial metadata: the status code, the content type, how the response may be cached, which security protections are in place, what compression was used, and more. Viewing them is the fastest way to understand how a server is configured and to debug caching, redirects, security, and performance issues.

How to use the headers viewer

It takes one step:

  • Enter the URL you want to inspect.
  • Choose GET (full request) or HEAD (headers only).
  • See the status code, HTTP version, redirect chain, and every response header.
  • Copy the raw headers or read the notes on common ones.

Headers worth checking for performance

A few headers have a big impact on speed:

  • Content-Encoding — gzip or br means the response is compressed (good).
  • Cache-Control and Expires — control how long browsers and CDNs cache the response.
  • ETag and Last-Modified — enable efficient cache revalidation.
  • Content-Type — the correct type (and charset) avoids rendering and sniffing issues.
  • Vary — tells caches which request headers change the response.

Headers worth checking for security

The same view reveals your security posture. Look for Strict-Transport-Security (HSTS) to force HTTPS, Content-Security-Policy to limit what can load, X-Content-Type-Options: nosniff to block MIME sniffing, and a sensible Referrer-Policy and Permissions-Policy. On the flip side, a verbose Server or X-Powered-By header leaks your tech stack and is often worth removing. Set-Cookie headers should carry Secure, HttpOnly, and SameSite flags.

Understanding status codes and redirects

The status code summarises the result: 2xx means success, 3xx is a redirect, 4xx is a client error like 404 Not Found, and 5xx is a server error. When a URL redirects, this tool shows the full chain of hops and where each one points, which is invaluable for spotting redirect loops, unnecessary extra hops that slow the page, or a mix of HTTP and HTTPS that hurts both speed and SEO. It also reports the HTTP version (HTTP/1.1, HTTP/2, or HTTP/3).

Pro tip

Use HEAD when you only care about the headers and want to avoid downloading the body — it is faster and lighter. Long redirect chains cost real time on every visit, so aim to redirect in a single hop straight to the final HTTPS URL. To dig deeper into specific areas, pair this with our Security Headers Checker and Cache-Control tools.

FAQ

Is this HTTP headers viewer free?
Yes. It is completely free and requires no account or sign-up. Enter a URL to see its response headers instantly.
What is the difference between GET and HEAD?
GET requests the full response including the body, while HEAD asks only for the headers. HEAD is faster and lighter when you only need to inspect headers.
How do I see a page's redirect chain?
Enter the starting URL. If it redirects, the tool lists each hop with its status code and target, so you can spot extra hops or redirect loops.
Which headers should I check for caching?
Look at Cache-Control, Expires, ETag, and Last-Modified. Good caching headers let browsers and CDNs reuse responses, which speeds up repeat visits.
How can I tell if a site uses HTTP/2 or HTTP/3?
The tool shows the HTTP version of the final response (for example HTTP/2). Newer versions generally improve performance through multiplexing and other optimisations.
Why can't the tool fetch some URLs?
The site may be down, blocking automated requests, requiring authentication, or the URL may be wrong. Make sure the page is publicly reachable over HTTP or HTTPS.
Does this change anything on the site?
No. It only makes a normal request and displays the headers the server returns. It does not modify the site in any way.

Related tools

Pro tip: pair this tool with PageSpeed Insights Checker and View Source Code for a faster SEO workflow.