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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.

Header type Request header
Forbidden header name yes

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

FeatureChromeFirefoxEdgeInternet ExplorerOperaSafari
Basic Support(Yes)(Yes)(Yes)(Yes)(Yes)(Yes)
FeatureAndroidChrome for AndroidEdge mobileFirefox for AndroidIE mobileOpera AndroidiOS Safari
Basic Support(Yes)(Yes)(Yes)(Yes)(Yes)(Yes)(Yes)

See also

Document Tags and Contributors

 Contributors to this page: fscholz
 Last updated by: fscholz,