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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
The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
| Feature | Chrome | Edge | Firefox | Internet Explorer | Opera | Safari | Servo |
|---|---|---|---|---|---|---|---|
| Basic Support | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) |
| Feature | Android | Chrome for Android | Edge Mobile | Firefox for Android | IE Mobile | Opera Mobile | Safari Mobile |
|---|---|---|---|---|---|---|---|
| Basic Support | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) |