What HTTP headers are sent by my browser?

# Header Name Header Value
1 GET /index.html HTTP/1.1
2 Connection keep-alive
Specifies options that are desired for the particular connection (and list of hop-by-hop request fields) and must not be communicated by proxies over further connections.
3 Cache-Control max-age=259200
Specifies cache control directives that must be obeyed by all caching mechanisms along the request/response chain.
4 X-Forwarded-For 10.3.91.132
A de facto standard for identifying the originating IP address of a client connecting to a web server through an HTTP proxy or load balancer
5 Via 1.1 squid-proxy-5b5d847c96-g4hz9 (squid/6.10)
Informs the server of proxies through which the request was sent. Used by gateways and proxies to indicate the intermediate protocols and recipients between the user agent and the server.
6 Host hdr.thatiuse.com
Specifies the host name of the server (for virtual hosting), and the TCP port number on which the server is listening. The port number may be omitted if the port is the standard port for the service requested. Mandatory since HTTP/1.1. If the request is generated directly in HTTP/2, it should not be used.
7 Cookie language=en
An HTTP cookie previously sent by the server with "Set-Cookie".
8 Referer http://hdr.thatiuse.com/
Referrer means the address (URI) of the previous web page from which a link to the currently requested page was followed.
9 Accept-Encoding gzip, br, zstd, deflate
Specifies which data format tranformations (content encodings), such as compression mechanisms, are acceptable for the response and to assign preferences to them. See HTTP compression.
10 User-Agent Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)
Contains information about the user agent (client) originating the request
11 Accept */*
Specifies which Internet media types (Content-Types) are acceptable for the response and to assign preferences to them. See Content negotiation.
12 Content-Length
Indicates the size (in bytes) of the entity-body that is sent.
13 Content-Type
Specifies the Internet media type (MIME type) of the entity-body that is sent (used with POST and PUT requests). Often includes a charset parameter specifying the character encoding.
Raw HTTP headers (.txt)