HTTP Headers Viewer

See what information your browser exposes to every website you visit. View your browser's request headers and inspect response headers from any URL.

100% Private — Header detection runs locally. Response headers are fetched directly in your browser.

Inspect Response Headers from a URL

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What Are HTTP Headers?

HTTP headers are metadata sent between your browser and web servers with every request and response. Request headers tell the server about your browser, language preferences, accepted content types, and more. Response headers tell your browser about caching, security policies, content type, and server configuration. Headers are invisible during normal browsing but reveal significant information about you.

Common Request Headers Explained

  • User-Agent — Identifies your browser, version, and operating system. Used for compatibility but also for fingerprinting.
  • Accept-Language — Your preferred languages. Reveals your location and nationality.
  • DNT (Do Not Track) — A signal requesting websites not track you. Not all websites honor this.
  • Connection Type — Your network connection type (WiFi, 4G, etc.). Available via the Network Information API.
  • Cookies Enabled — Whether your browser accepts cookies. Cookies are the primary tracking mechanism on the web.
  • Referrer Policy — Controls what URL information is sent when you click links.

Common Response Headers

Response headers sent by web servers include security headers (Content-Security-Policy, Strict-Transport-Security, X-Frame-Options), caching headers (Cache-Control, ETag, Expires), content headers (Content-Type, Content-Length), and server identification (Server, X-Powered-By). Missing security headers can indicate a poorly configured server.

Why Should You Care About HTTP Headers?