SP.ClientContext.serverLibraryVersion property (sp.js)
Gets the build version of Microsoft.SharePoint.Client.ServerRuntime.dll on the server.
Applies to: apps for SharePoint | SharePoint Foundation 2013 | SharePoint Server 2013
var value = SP.ClientContext.get_serverLibraryVersion()
Return value
String
The build version of Microsoft.SharePoint.Client.ServerRuntime.dll on the server.