The Connection general header controls whether or not the network connection stays open after the current transaction finishes. If the value sent is keep-alive, the connection is persistent and not closed, allowing for subsequent requests to the same server to be done.
Except for the standard hop-by-hop headers (Keep-Alive, Transfer-Encoding, TE, Connection, Trailer, Upgrade, Proxy-Authorization and Proxy-Authenticate), any hop-by-hop headers used by the message must be listed in the Connection header, so that the first proxy knows he has to consume them and not to forward them further. Standard hop-by-hop headers can be listed too (it is often the case of Keep-Alive, but this is not mandatory.
| Header type | General header |
|---|---|
| Forbidden header name | no |
Syntax
Connection: keep-alive Connection: close
Directives
close- Indicates that either the client or the server would like to close the connection. This is the default on HTTP/1.0 requests.
- any comma-separated list of HTTP headers [Usually
keep-aliveonly] - Indicates that the client would like to keep the connection open. Having a persistent connection is the default on HTTP/1.1 requests. The list of headers are the name of the header to be removed by the first non-transparent proxy or cache in-between: these headers define the connection between the emitter and the first entity, not the destination node.
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.