WebSocket: protocol property

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.

Note: This feature is available in Web Workers.

The WebSocket.protocol read-only property returns the name of the sub-protocol the server selected; this will be one of the strings specified in the protocols parameter when creating the WebSocket object, or the empty string if no connection is established.

Value

A string.

Specifications

Specification
WebSockets Standard
# ref-for-dom-websocket-protocol①

Browser compatibility

BCD tables only load in the browser

See also