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The HTTP 101 Switching Protocols response code indicates the protocol the server is switching to as requested by a client which sent the message including the Upgrade request header.

The server includes in this response an Upgrade response header indicate the protocol it switched to. The process is described in detail in the article Protocol upgrade mechanism.

Status

101 Switching Protocols

Examples

Switching protocols might be used with WebSockets.

HTTP/1.1 101 Switching Protocols
Upgrade: websocket 
Connection: Upgrade

Specifications

Specification Title
RFC 7231, section 6.2.2: 101 Switching Protocol Hypertext Transfer Protocol (HTTP/1.1): Semantics and Content

See also

Document Tags and Contributors

 Contributors to this page: amjad, Sheppy, solvaholic, teoli, fscholz
 Last updated by: amjad,