Keeping Browser Tabs in Sync with Broadcast Channel API 🔄✨

#javascript #frontend #sync #browser

Ever open multiple tabs of the same web app and notice things don’t stay in sync? Whether it’s your shopping cart, notifications, or form progress, inconsistent data across tabs can be frustrating for users.

The Challenge

Each browser tab runs independently. Without communication, updates in one tab don’t reflect in others, causing confusion and poor user experience.

The Simple Fix: Broadcast Channel API

This built-in browser API lets tabs communicate instantly over a shared “channel.” When one tab updates data, it broadcasts a message others receive — keeping everything perfectly synchronized.

How It Works (In a Nutshell)

const channel = new BroadcastChannel('app-sync');

channel.onmessage = (event) => {
  console.log('Update from another tab:', event.data);
  // Sync local state here
};

function updateData(newData) {
  // Local update
  channel.postMessage(newData); // Notify other tabs
}