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HTTP Headers
View the raw response headers returned by any server.
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About HTTP Headers
HTTP Headers shows every header a server actually sent back for a given request, along with the status code, HTTP version and any redirects followed along the way.
This is the tool to reach for when debugging caching behaviour, checking what a CDN or reverse proxy is adding or stripping from a response, or simply seeing exactly what a server returns without opening a terminal.
Because redirects are followed automatically, the result also shows the final URL a request actually lands on, which is useful for spotting an unnecessarily long redirect chain worth shortening at the source.
Tutorials
HTTPS and TLS, What the Padlock Is Actually Telling YouWhat encryption in transit protects against, what it does not, and why a valid certificate and a security header check both matter.6 min readReading HTTP Response HeadersWhat the headers a server sends back with every response actually mean, beyond the security specific ones, and what they can tell you about how a site is built.6 min readHow HTTP Redirects Work, and Why the Chain MattersThe difference between the common redirect status codes, why a long redirect chain is a real cost, and how to check one properly.5 min readHow to Tell What a Website Is Built WithThe headers, markup patterns and script sources that reveal a site's CMS, framework, CDN and analytics setup, and how reliable each signal actually is.6 min read