React Performance Optimization: A Practical Guide

# React Performance Optimization

Performance matters. A slow application frustrates users and hurts business metrics. Here are battle-tested strategies for keeping React apps fast.

Profiling First

Never optimize blindly. Use React DevTools Profiler and browser performance tools to identify actual bottlenecks before making changes.

Memoization Strategy

Use `React.memo`, `useMemo`, and `useCallback` strategically — not everywhere. Premature memoization adds complexity without benefit.

Virtualization for Long Lists

For lists with 100+ items, use virtualization libraries like `react-window` or `tanstack-virtual` to only render visible items.

Code Splitting

Use `React.lazy` and dynamic imports to split your bundle. Load heavy components only when they're needed.

Key Takeaways

- Profile before optimizing - Memoize strategically, not universally - Virtualize long lists - Split code by route and heavy components