React Interview Preparation Roadmap
A roadmap from Basic → Advanced for React interview preparation. For 1–3 years of experience, a React interview usually covers:
- Core rendering model (Virtual DOM, reconciliation, keys)
- Components, props and state
- Hooks (and the rules behind them)
- State management beyond
useState - Routing
- Performance optimisation
- Modern React (React 19 features)
The approach that works:
- Learn topic
- Understand why React does it that way
- Write a small example
- Answer the interview question out loud
- Build one small feature using it
Suggested Learning Order
Version Note
These notes target React 19 (Server Components stable since December 2024) and React Compiler v1.0 (stable since October 2025). Where an answer changed between React 18 and 19, both are shown — interviewers still ask the React 18 version.
What Interviewers Actually Test
| Area | What they are really checking |
|---|---|
| Virtual DOM / keys | Do you understand re-render vs re-paint |
| Hooks rules | Do you know why hooks break on conditionals |
useEffect | Can you avoid infinite loops and stale closures |
useMemo / useCallback | Do you optimise on evidence, or by reflex |
| Context vs Redux | Can you pick the right tool, not the popular one |
| Reconciliation | Can you explain why React is fast |