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/HTTP

Host

The Host request header specifies the domain name of the server (for virtual hosting), and (optionally) the TCP port number on which the server is listening.

If no port is given, the default port for the service requested (e.g., "80" for an HTTP URL) is implied.

A Host header field must be sent in all HTTP/1.1 request messages. A 400 (Bad Request) status code will be sent to any HTTP/1.1 request message that lacks a Host header field or contains more than one.

Syntax

Host: <host>:<port>

Directives

<host>
the domain name of the server (for virtual hosting).
<port> Optional
TCP port number on which the server is listening.

Examples

Host: developer.cdn.mozilla.net

Specifications

Specification Title
RFC 7230, section 5.4: Host Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing

Browser compatibility

Feature Chrome Firefox Edge Internet Explorer Opera Safari
Basic Support (Yes) (Yes) (Yes) (Yes) (Yes) (Yes)
Feature Android Chrome for Android Edge mobile Firefox for Android IE mobile Opera Android iOS Safari
Basic Support (Yes) (Yes) (Yes) (Yes) (Yes) (Yes) (Yes)

See also

© 2005–2017 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Host