HTTP Header Checker.
See what a web server sends back for any address: the status code, every redirect on the way, the security headers, caching and compression, and how fast it answers.
100% free, no sign-up. To stop automated scanning, each browser can run up to 10 scans per tool every 3 hours; only that count is kept (privacy).
What Is an HTTP Header Checker?
Every time a browser asks for a page, the server answers with the page and a set of HTTP headers: short lines that say how the answer should be handled. An HTTP header checker shows those lines for any address, together with the status code and every redirect on the way.
Headers tell you if the page was found (200) or moved (301 or 302), how long it may be cached, whether it was compressed, which software answered and which protections the site asks the browser to apply, such as HSTS and Content-Security-Policy.
This tool makes the request from our server, not your browser, so extensions, cookies, caches and logins do not change what you see. It follows up to six redirects and shows the time to first byte.
What the Server Really Sends.
The request is made from our server, not your browser, so you see the plain answer without extensions, caches or logins in the way.
Status and redirects
The HTTP status code and each redirect, such as http to https or example.com to www, with the address and time of every step.
Security headers
Whether HSTS, Content-Security-Policy, X-Content-Type-Options, X-Frame-Options, Referrer-Policy and Permissions-Policy are set.
Speed and caching
Time to first byte, connect and TLS time, the cache rules and whether the response is compressed.
Server details
The server software and content type, plus every response header, for debugging.
Common Problems and Fixes.
Headers explain most "why is my site slow or redirecting oddly" questions.
The page redirects in a loop
Two rules send visitors back and forth, often HTTP to HTTPS or www to non-www set in two places. Keep each redirect in one place, such as the server config, and test again.
There are too many redirects
Every hop adds delay and may lose search value. Link to the final address and redirect the old address straight to it in one step.
Security headers are missing
Add Strict-Transport-Security, X-Content-Type-Options, Referrer-Policy, Permissions-Policy, a frame rule and a Content-Security-Policy in the server config or .htaccess.
The time to first byte is slow
A high value points to slow server work, usually uncached PHP or database queries. Add page caching, use a CDN or move to a faster server.
Compression is off
Turn on gzip or Brotli for text files. A compressed answer carries a Content-Encoding header and is much smaller to send.
Cache headers are wrong or missing
Static files such as images and fonts should carry Cache-Control with a long max-age. Pages that change often should not be cached for long.
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Frequently Asked Questions
Quick answers about this tool.
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