HTTP Headers Viewer

Review a safe selection of headers received with this request, including User-Agent and language preferences.

Loading request headers...

Common HTTP Headers

User-Agent

Browser name, version, and operating system

Accept-Language

Your preferred language(s) for content

Referer

The page you came from (can reveal browsing history)

DNT (Do Not Track)

Your tracking preference (often ignored by websites)

Privacy Implications

HTTP headers reveal a surprising amount about you. Your User-Agent alone can narrow down your device to a small group of users. Combined with language preferences and other headers, websites can often uniquely identify you.

Headers marked with "Privacy Risk" are particularly identifying. The Referer header is especially concerning as it reveals which site you were previously visiting.

Frequently Asked Questions

What are HTTP headers?

HTTP headers are key-value pairs sent with web requests and responses. They can carry content preferences, caching instructions, browser information, and other request metadata.

Does this page display every request header?

No. The server receives the headers attached to this request, but this viewer returns only an allowlisted selection of ordinary browser and content-negotiation headers. It does not return cookies, authorization credentials, or internal hosting headers.

How can headers be used for tracking?

Headers like User-Agent, Accept-Language, and Accept-Encoding create a partial fingerprint. Combined with other data, they help identify unique visitors. Some headers like Referer also reveal your browsing history.

Can I modify or hide HTTP headers?

Browser extensions can modify some headers. Privacy browsers like Tor standardize headers to reduce fingerprinting. However, completely hiding headers would break most websites.