React Performance Optimization: 12 Tips Every Developer Should Know

Source: Dev.to

Introduction

React apps often become slower as they grow — unnecessary re‑renders, heavy bundles, and sluggish interactions all contribute to poor performance. The good news? Most bottlenecks can be fixed with simple optimization techniques. Here are 12 essential tips every React developer should know.

Tips

1. Use React.memo

Prevents a component from re‑rendering when its props haven’t changed.

2. Use useCallback and useMemo

Memoize functions and heavy computations to avoid recreating them on every render.

3. Code‑split with React.lazy

Load components only when needed to keep bundles small and the initial load fast.

4. Virtualize large lists

Use libraries like react-window to render only visible items instead of thousands of DOM nodes.

5. Avoid anonymous functions in JSX

Create functions outside JSX to avoid new references on each render.

6. Keep state local

Avoid lifting state too high — it causes entire component trees to re‑render unnecessarily.

7. Optimize context usage

Large contexts trigger large re‑render waves. Split context or use lightweight alternatives like Zustand, Jotai, or Recoil.

8. Memoize expensive calculations

Wrap heavy logic inside useMemo to avoid recalculating on every update.

9. Use production builds

Production mode removes warnings and optimizes performance. Always deploy with npm run build.

10. Use the React Profiler

Use the React DevTools Profiler to find slow components, wasted renders, and bottlenecks.

11. Keep props stable

Inline objects/arrays create new references. Memoize them to prevent unnecessary re‑renders.

12. Debounce or throttle high‑frequency events

Reduce DOM updates by limiting how often input, scroll, or mouse events trigger state updates.

Best Practices

• Keep components small and focused.
• Use SSR (e.g., Next.js, Remix) for faster load times.
• Analyze bundle size regularly.
• Cache API requests with SWR or React Query.
• Remove heavy, unused dependencies.

Conclusion

React performance optimization is not about a single trick — it’s a collection of small, intentional choices. These 12 tips help reduce wasted renders, improve responsiveness, and keep your application snappy.