SignalR vs Socket.IO: What are the differences?
Developers describe SignalR as "A new library for ASP.NET developers that makes developing real-time web functionality easy". SignalR allows bi-directional communication between server and client. Servers can now push content to connected clients instantly as it becomes available. SignalR supports Web Sockets, and falls back to other compatible techniques for older browsers. SignalR includes APIs for connection management (for instance, connect and disconnect events), grouping connections, and authorization. On the other hand, Socket.IO is detailed as "Realtime application framework (Node.JS server)". Socket.IO enables real-time bidirectional event-based communication. It works on every platform, browser or device, focusing equally on reliability and speed.
SignalR and Socket.IO belong to "Realtime Backend / API" category of the tech stack.
"Supports .NET server" is the top reason why over 7 developers like SignalR, while over 186 developers mention "Real-time" as the leading cause for choosing Socket.IO.
SignalR and Socket.IO are both open source tools. Socket.IO with 46.7K GitHub stars and 8.53K forks on GitHub appears to be more popular than SignalR with 7.73K GitHub stars and 2.19K GitHub forks.
According to the StackShare community, Socket.IO has a broader approval, being mentioned in 555 company stacks & 385 developers stacks; compared to SignalR, which is listed in 20 company stacks and 16 developer stacks.