HTTP Header Checker

An HTTP header checker shows the raw response headers a server returns for a URL. Headers reveal caching rules, compression, content type, security settings and indexing directives.

This tool fetches the address you enter once, from our server, and reports what a crawler would receive. The URL is not stored; only a short-lived rate-limit counter is kept. Results show the page at the moment of the check and can differ from what a logged-in browser or a bot with different headers sees.

How to read the result and act on it

Scan the response for the headers that matter. Status line first, then content-type, which should match the file, and cache-control or expires, which show how long browsers and CDNs may reuse the response. Look for content-encoding to confirm gzip or br compression, and for x-robots-tag in case an indexing directive is being sent. A link header may carry a canonical or preload hint. Security headers such as strict-transport-security appear here too. If something looks wrong, trace where it is set: the origin server, a plugin, a CDN or a proxy. Adjust it there, clear caches, and recheck the same URL.

Common mistakes to avoid

A common mistake is assuming the headers seen in a browser tool match what a crawler gets. Cached CDN responses, bot rules and user agent differences can change them. Another is setting cache-control too long on HTML, so updates take days to appear, or too short on static assets, which wastes bandwidth. Wrong content-type values, such as text/plain for HTML, can stop proper rendering. Leaving a staging x-robots-tag noindex header in production is an expensive oversight. Also avoid exposing detailed server version strings in headers. Remember that a single request shows one moment, so compare a few URLs of different types.

Which headers matter for SEO?

Status code, Location (for redirects), X-Robots-Tag, Content-Type, Cache-Control and Content-Encoding.

Why do headers differ from what my browser shows?

Servers can respond differently based on user agent, cookies or location.

How do I view HTTP response headers for a URL?

Use a header checker, run curl -I in a terminal, or open browser DevTools, select the Network tab, click the document request and read Response Headers. Each method shows the headers the server sent for that request.

What does cache-control mean for SEO?

Cache-control tells browsers and CDNs how long to reuse a response. It affects speed and bandwidth rather than rankings directly, but good caching of static files helps pages load faster for repeat visitors, which supports page experience.

• X-Robots-Tag Checker: Check HTTP headers for X-Robots-Tag directives that control indexing of pages and files.
• Security Headers Checker: Check for HSTS, Content-Security-Policy, X-Content-Type-Options, frame and referrer headers.
• Compression Checker: Check whether a page is served with gzip or Brotli and how much it saves.

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