What is HTTP Header?

HTTP Header is a way for the client and server to exchange data in key-value pair format during HTTP requests and responses. It is an important part of the HTTP protocol.

HTTP headers not only allow clients and website servers to communicate more efficiently, but also influence their behavior. For example, define caching, identity authentication, session management, connection status, encoding and decoding, etc.

What can HTTP Header Online Check Tool do?

HTTP Header Online Check Tool is an HTTP response header analysis tool used to view the header information of the website server response. The detection tool supports GET, POST, HEAD, PUT, PATCH, DELETE, CONNECT, OPTIONS, TRACE requests, and also supports viewing Response Debug information.

After entering a domain name, IP address or URL to be detected, the detection tool issues a GET / POST / HEAD / OPTIONS / PUT / PATCH / DELETE / CONNECT / TRACE request, obtains the response from the website server, and analyzes the header.

List of commonly used HTTP headers

WWW-Authenticate Authorization Proxy-Authenticate Proxy-Authorization Age Cache-Control Clear-Site-Data Expires Pragma Warning Accept-CH Save-Data Last-Modified ETag If-Match If-None-Match If-Modified-Since If-Unmodified-Since Vary Delta-Base Connection Keep-Alive Accept Accept-Encoding Accept-Language A-IM IM Expect Max-Forwards Cookie Set-Cookie Access-Control-Allow-Origin Access-Control-Allow-Credentials Access-Control-Allow-Headers Access-Control-Expose-Headers Access-Control-Max-Age Access-Control-Request-Headers Access-Control-Request-Method Timing-Allow-Origin Content-Disposition Content-Length Content-Type Content-Encoding Content-Language Content-Location Forwarded X-Forwarded-For X-Forwarded-Host X-Forwarded-Proto Via Location From Host Referer Referrer-Policy User-Agent Allow Server Accept-Ranges Range If-Range Content-Range Cross-Origin-Embedder-Policy Cross-Origin-Opener-Policy Cross-Origin-Resource-Policy Content-Security-Policy Content-Security-Policy-Report-Only Expect-CT Strict-Transport-Security Upgrade-Insecure-Requests X-Content-Type-Options X-Frame-Options X-Powered-By X-XSS-Protection Sec-Fetch-Site Sec-Fetch-Mode Sec-Fetch-User Sec-Fetch-Dest NEL Transfer-Encoding TE Trailer Sec-Websocket-Accept Alt-Svc Date Link Retry-After Server-Timing Sourcemap Upgrade X-DNS-Prefetch-Control X-Request-ID X-Robots-Tag X-UA-Compatible