Performance optimization in React is often surrounded by myths. Developers routinely wrap every single component in React.memo, wrap every function in useCallback, and wonder why their application is still sluggish or memory-heavy.
Premature optimization can actually degrade app performance and clutter your codebase. To build fast React applications, you need techniques that address actual bottlenecks: unnecessary re-renders, unoptimized state placement, oversized bundles, and main-thread blocking.
Here are five practical React performance optimization techniques that deliver measurable results in production.
1. Push State Down (Fix Rerender Cascades)
Before reaching for useMemo or React.memo, evaluate your state placement. When state lives too high up in the component tree, every state update forces the entire sub-tree to re-render.
