What browsers support WebSockets?

WebSockets have universal browser support across all modern browsers since 2012. All versions of Chrome (from v16), Firefox (from v11), Safari (from v7), Edge (from v12), and Opera support the WebSocket API. Internet Explorer 10 and 11 also support WebSockets. Mobile browsers — Mobile Safari (iOS 6+), Android Browser (4.4+), and Chrome for Android — all support WebSockets. According to CanIUse.com, WebSocket support is at ~97%+ of global browser usage. The only environments where WebSockets might be blocked are restrictive corporate firewalls/proxies that only allow standard HTTP traffic, or very old embedded browsers in IoT devices. For these edge cases, Socket.IO's long-polling fallback or SSE provides the necessary compatibility.