HTTP Headers Lookup
Reference guide for common HTTP request, response, and general headers.
39 headers shown
About HTTP headers
HTTP headers are key-value metadata passed between client and server in every request and response. Request headers describe the client and the resource it wants; response headersdescribe the server's response. General headers can appear in both. Security headers like Content-Security-Policy, Strict-Transport-Security, and X-Frame-Options are response headers that browsers act on automatically. Related: URL encoder/decoder and CORS header generator.
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