HTTP Response Headers Inspector

Check HTTP status codes (200, 301, 404), server technologies, compression, and security headers (CSP, HSTS).

📑

HTTP Response for facebook.com

HTTP/1.1 400 Bad Request
Header Field Value
Status HTTP/1.1 400 Bad Request
Location https://www.facebook.com/
Strict-Transport-Security max-age=15552000; includeSubDomains, max-age=15552000; preload
Content-Type text/html; charset="utf-8", text/html; charset="utf-8"
X-FB-Debug OvMv2Q7XidfhWMzeofTGYPp/hgEv9z1qzDQ08Oc9PPbg7BEpIIp9R06HrCjCMeFEJbFRfD0gRftBVniZG1ZKKw==, K9+BwJbPfIeX6KPJ2cr+z3C19E+k3HboNiOtzWs8zTLDsiiL7zecWDCs/P4vb7JtgeffALcIODt9VznwvGDWCw==
Date Wed, 07 Oct 2026 02:00:59 GMT, Wed, 07 Oct 2026 02:01:00 GMT
X-FB-Connection-Quality EXCELLENT; q=0.9, rtt=26, rtx=0, c=10, mss=1380, tbw=3449, tp=-1, tpl=-1, uplat=152, ullat=0, GOOD; q=0.7, rtt=54, rtx=0, c=10, mss=1380, tbw=3448, tp=-1, tpl=-1, uplat=274, ullat=0
Alt-Svc h3=":443"; ma=86400, h3=":443"; ma=86400
Connection close, close
Content-Length 0
Pragma no-cache
Cache-Control private, no-cache, no-store, must-revalidate
Expires Sat, 01 Jan 2000 00:00:00 GMT
content-security-policy default-src blob: 'self' https://*.fbsbx.com *.facebook.com *.fbcdn.net *.facebook.net *.whatsapp.com *.whatsapp.net;script-src *.facebook.com *.fbcdn.net *.facebook.net 127.0.0.1:* 'nonce-TKxnA3JA' blob: 'self' connect.facebook.net 'wasm-unsafe-eval' https://accounts.google.com https://*.google-analytics.com *.google.com;style-src *.fbcdn.net data: *.facebook.com 'unsafe-inline' https://accounts.google.com https://fonts.googleapis.com;connect-src *.facebook.com facebook.com *.fbcdn.net *.facebook.net wss://*.facebook.com:* wss://*.whatsapp.com:* wss://*.fbcdn.net attachment.fbsbx.com ws://localhost:* blob: *.cdninstagram.com 'self' http://localhost:3103 wss://gateway.facebook.com wss://edge-chat.facebook.com wss://snaptu-d.facebook.com wss://kaios-d.facebook.com/ v.whatsapp.net *.fbsbx.com *.fb.com *.instagram.com *.ipification.com https://accounts.google.com https://*.google-analytics.com;font-src data: *.facebook.com *.fbcdn.net *.fbsbx.com https://fonts.gstatic.com;img-src *.fbcdn.net *.facebook.com data: https://*.fbsbx.com facebook.com *.cdninstagram.com fbsbx.com fbcdn.net connect.facebook.net blob: android-webview-video-poster: *.whatsapp.net *.fb.com *.oculuscdn.com *.tenor.co *.tenor.com *.giphy.com https://trustly.one/ https://*.trustly.one/ https://paywithmybank.com/ https://*.paywithmybank.com/ https://www.googleadservices.com https://googleads.g.doubleclick.net https://*.google-analytics.com;media-src *.cdninstagram.com blob: *.fbcdn.net *.fbsbx.com www.facebook.com *.facebook.com data: *.tenor.co *.tenor.com https://*.giphy.com;child-src data: blob: 'self' https://*.fbsbx.com *.facebook.com *.fbcdn.net;frame-src *.facebook.com *.fbsbx.com fbsbx.com data: www.instagram.com *.fbcdn.net accounts.meta.com *.accounts.meta.com *.fbthirdpartypixel.com *.ipification.com https://trustly.one/ https://*.trustly.one/ https://paywithmybank.com/ https://*.paywithmybank.com/ https://www.googleadservices.com https://googleads.g.doubleclick.net https://www.google.com https://td.doubleclick.net *.google.com *.doubleclick.net;manifest-src data: blob: 'self' https://*.fbsbx.com *.facebook.com *.fbcdn.net;object-src data: blob: 'self' https://*.fbsbx.com *.facebook.com *.fbcdn.net;worker-src blob: *.facebook.com data:;block-all-mixed-content;upgrade-insecure-requests;
document-policy include-js-call-stacks-in-crash-reports
nel {"report_to":"network-errors","max_age":604800,"failure_fraction":0.25}
X-Frame-Options DENY
X-Content-Type-Options nosniff
X-XSS-Protection 0
reporting-endpoints coop_report="https://www.facebook.com/browser_reporting/coop/?minimize=0", default="https://www.facebook.com/ajax/browser_error_reports/?device_level=unknown&brsid=7693740103911370027&cpp=C3&cv=1049516966&st=1791338460454"
report-to {"max_age":2592000,"endpoints":[{"url":"https:\/\/www.facebook.com\/browser_reporting\/coop\/?minimize=0"}],"group":"coop_report","include_subdomains":true}, {"max_age":259200,"endpoints":[{"url":"https:\/\/www.facebook.com\/ajax\/browser_error_reports\/?device_level=unknown&brsid=7693740103911370027&cpp=C3&cv=1049516966&st=1791338460454"}]}, {"max_age":604800,"endpoints":[{"url":"https:\/\/www.facebook.com\/ajax\/browser_error_reports\/?device_level=unknown&brsid=7693740103911370027&cpp=C3&cv=1049516966&st=1791338460454"}],"group":"network-errors"}
cross-origin-opener-policy same-origin-allow-popups
Vary Sec-Fetch-Site, Sec-Fetch-Mode, Accept-Encoding
origin-agent-cluster ?1
Transfer-Encoding chunked
Proxy-Status http_request_error; e_proxy="AcTJmBdDDPA-4j9_iU3dvM1wm3G4WdjiV9zN1yhEI2h5G33ySn3L3u-gmMeC4cwd_BLAJHIXDfyKqiiYyaTM"; e_fb_twtaskhandle="AcRRnmkfKppNcrc7wbyp8G1fBNcsxDIvEaTFuYPGriQaNf4gFOL5c-M27WXE3Rb-WZiGHfci9Ewa3k1bRmb9qnTn7WRxUrK10VHJrAAFYXo5ABc"; e_upip="AcRmaDxfkJ0gVN-cwZVK9B5ykigVjsGntp4yE6ea1gg_yL8Z5Tyy9vAxmkNs1zA16dE0dt0kADHDh9U9l_qxvI7UwT9_mI2_-bKyE_GgovY"; e_fb_zone="AcSYxyuKu5XIeQcEjGdXtBOOOCJHLazbrh5x2p2Zp41H1q2wFuJI9RnppOgDeNlk"; e_clientaddr="AcSL8Eim39UJ9TdGbsrUzAI4rqytgFYJYqXKhv73JYH7Y-5dugCX_kpaEU9SUtw0qMQysuKEcgt5gXyoRQ2kY2muy5J0x9YQeSu83AaocFMo5FBX"; e_fb_vipaddr="AcQEAzqp5Q00BTXRCh7lnAWCn_IlRClZaG1uYnXEw8wHOLtHtYSVc2OiOAj-P0PBEJNcdjtpMn9TXOq_gl0MiUbXwGYkGyxkxS34MRi5", http_request_error; e_proxy="AcRTA5jz1JfNzEetxBw-D-D6koDIY-rCsm-oQlFd4g9vR5V71200NnUUlUnoTDZwkGM7XPw8NwPdoQc"; e_fb_twtaskhandle="AcRZPOh8uYncWCHMouLyF7MdYpHlbeZ33Pn5ZYejm0fpJepBjd0WeJxXG2QWQfrswiPNQEKGbfVlhDD2NFnMnzrW9Qmx0eXGoycb"; e_upip="AcSYmKPvHTwcF_Y2KeFec0yBWHMsqyvsATVU6mNN8Moe2ie1vbhGT_RShRgjTVzm9GnJR9HIFaOU3wY85c680g0MvY5Y2jIl3d2FjInP"; e_fb_zone="AcQV4jALexEKWmABoKVINLrsek3MZA8helNFkI1ugywjyop8LlCcNcFINGaVPA"; e_clientaddr="AcToC_MP2EXFyp34NU7N44jsOe4FSv_5plPqNlaAtZGsM7qNss-ajfxnP-yf-egCHLNVFdYCe-R_AWusexk"; e_fb_vipaddr="AcS7B5_AyaLgv9MP0QoekakVTv10BwN6d-mYvJ2Io3MG31dsq8dnnSQ6V0txZDrFf6HDMPZ-"
Server-Timing slb_crtt;dur=54,slb_srtt;dur=-1,slb_req_start;dur=1791338460296500,slb_srv_hdr_rcvd;dur=274707,slb_cli_body_rcvd_first;dur=-1,slb_cli_body_rcvd_last;dur=-1,slb_conn_lat;dur=0,slb_ssl;dur=457,slb_rule_lat;dur=0