The Via general header is added by proxies, both forward and reverse proxies, and can appear in the request headers and the response headers. It is used for tracking message forwards, avoiding request loops, and identifying the protocol capabilities of senders along the request/response chain.

Header type General header
Forbidden header name yes

Syntax

Via: [ <protocol-name> "/" ] <protocol-version> <host> [ ":" <port> ]
or
Via: [ <protocol-name> "/" ] <protocol-version> <pseudonym>

Directives

<protocol-name>
Optional. The name of the protocol used, such as "HTTP".
<protocol-version>
The version of the protocol used, such as "1.1".
<host> and <port>
Public proxy URL and port.
<pseudonym>
Name/alias of an internal proxy.

Examples

Via: 1.1 vegur
Via: HTTP/1.1 GWA
Via: 1.0 fred, 1.1 p.example.net

Specifications

Specification Title
RFC 7230, section 5.7.1: Via Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing

Browser compatibility

FeatureChromeEdgeFirefoxInternet ExplorerOperaSafari
Basic support Yes Yes Yes Yes Yes Yes
FeatureAndroid webviewChrome for AndroidEdge mobileFirefox for AndroidOpera AndroidiOS SafariSamsung Internet
Basic support Yes Yes Yes Yes Yes Yes Yes

See also

Document Tags and Contributors

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