React Interview Questions
React interview questions on hooks, components, state and rendering — the most-requested front-end framework in technical interviews.
Topics
- HooksuseState, useEffect and the rules of hooks — the foundation of modern function-component React. 7 subtopics
- ComponentsJSX syntax, props, event handling, conditional rendering, and lists — the building blocks of every React UI. 5 subtopics
- State and Data FlowLifting state, the Context API, controlled vs. uncontrolled components, and solutions to prop drilling — how data moves through a React application. 4 subtopics
- Rendering and PerformanceVirtual DOM, reconciliation, React.memo, useMemo/useCallback patterns, code splitting with lazy/Suspense, and concurrent rendering — how React decides what to paint and how to keep it fast. 5 subtopics
- RoutingReact Router v6 fundamentals, dynamic and nested routes, navigation hooks (useNavigate, useParams, useLocation), and protecting routes with auth guards. 4 subtopics
- State ManagementRedux Toolkit, Zustand, Context vs Redux trade-offs, and async state management with React Query — patterns for managing global and server state in production React apps. 4 subtopics
- PatternsCompound components, render props, HOCs, error boundaries, portals, refs, forwardRef, and useImperativeHandle — React advanced composition patterns for building flexible, reusable, and production-grade component APIs. 5 subtopics
- TestingReact Testing Library, component interaction testing, mocking async operations, and testing custom hooks — everything you need to write confident, maintainable tests for React applications. 4 subtopics