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.
Inspect Response Headers from a URL
How HTTP Headers Viewer Works
Discover what HTTP headers your browser sends and receives. View User-Agent, Accept-Language, cookies, DNT, and response headers from any URL. and. Use the tool above to get your results instantly — everything runs in your browser with no data sent to any server.
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?
- Headers expose your browser, OS, language, and connection type to every website
- Combining headers creates a semi-unique profile for fingerprinting
- Missing security response headers leave you vulnerable to attacks
- Understanding headers helps you make informed privacy decisions
- Developers use headers for debugging, caching optimization, and security hardening
Getting the Most from This Tool
Start by exploring the default settings to understand what the tool offers, then customize the inputs to match your specific needs. Use the results as a starting point for deeper analysis or decision-making. Bookmark this page for quick access in the future. All processing happens in your browser, so your data stays private and the tool works even without an internet connection after the initial page load.
Frequently Asked Questions
What are HTTP headers?
HTTP headers are metadata sent between your browser and web servers with every request. They include information like your browser type, preferred language, cookie settings, and more. Servers also send headers back with caching rules, security policies, and content type info.
Can websites see my request headers?
Yes. Every website you visit receives your request headers including User-Agent, Accept-Language, DNT setting, and any cookies for that domain. This is how the web works — headers are sent automatically with every request.
Why can I not see all response headers?
Due to browser security (CORS), JavaScript can only read response headers that the server explicitly allows. Some servers restrict which headers are visible in cross-origin requests. Use browser developer tools (F12, Network tab) to see all headers.
What security headers should a website have?
Critical security headers include Strict-Transport-Security (forces HTTPS), Content-Security-Policy (prevents XSS), X-Frame-Options (prevents clickjacking), and X-Content-Type-Options (prevents MIME sniffing). Missing these headers indicates weaker security.
How can I hide my HTTP headers?
You cannot completely hide headers, but you can minimize information exposure. Use a VPN, install a User-Agent spoofing extension, enable Do Not Track, block third-party cookies, and use a privacy-focused browser like Firefox or Brave.
Does this tool store my headers?
No. All header detection happens locally in your browser. For response header checks, the fetch request goes directly from your browser to the target URL. We do not proxy, store, or log any data.