Advanced React Performance Optimization

Performance is critical for user experience. In this guide, we'll explore advanced techniques to make your React applications lightning fast.

Understanding React Performance

React is fast by default, but as applications grow, performance bottlenecks can emerge. The key is understanding when and why React re-renders components.

Optimization Techniques

1. Memoization

Use React.memo(), useMemo(), and useCallback() to prevent unnecessary re-renders:

const MemoizedComponent = React.memo(({ data }) => {
  return {data};
});

const ExpensiveCalculation = ({ items }) => {
  const total = useMemo(() => {
    return items.reduce((sum, item) => sum + item.price, 0);
  }, [items]);
  
  return Total: {total};
};

2. Code Splitting

Split your bundle using dynamic imports and React.lazy():

const LazyComponent = React.lazy(() => import('./HeavyComponent'));

function App() {
  return (
    Loading...

}>
      
    
  );
}

3. Virtualization

For long lists, use virtualization libraries like react-window or react-virtualized to render only visible items.

Performance Monitoring

Always measure performance with React DevTools Profiler and Chrome DevTools to identify real bottlenecks before optimizing.