React Interview Questions for Freshers 2026

React is one of the most demanded frontend skills in India's fresher hiring market right now. This article covers the React interview questions freshers commonly face in 2026, from conceptual rounds to live coding screens, with answers and MCQ practice.

Candidate accounts suggest the React floor differs by company type. At product companies, recent React features come up more often, Server Components versus Client Components, the use hook for promise unwrapping, and useActionState for form mutations are topics candidates have reported. Interviewers also tend to push past behavior into the React-internal reason, for example why a useEffect cleanup function runs before the next effect. At service companies (TCS, Wipro, Infosys), the staples still dominate: class-versus-function components, the virtual DOM, and Redux flow. Prepare both layers and confirm the stack the company actually uses.

What Are React Interviews Like for Freshers in 2026?

React interviews at product companies (Swiggy, Zomato, Razorpay, Cred, Groww) and service companies (TCS, Wipro, Tech Mahindra) differ sharply in depth. Freshers without prior internship experience are tested on:

• Core React concepts: JSX, components, props, state
• Hooks: useState, useEffect, useCallback, useMemo, useRef
• Lifecycle methods vs hooks equivalents
• Virtual DOM internals
• Performance optimisation basics
• One to two live coding tasks on platforms like HackerRank or CodePair

Companies hiring React freshers in 2026 include Juspay, Razorpay, BrowserStack, smallcase, Swiggy, and several SaaS startups. Service-sector companies like Wipro and Tech Mahindra have added frontend-specific tracks in their 2025–26 drives.

Topic-Wise Frequency Analysis (2023–2025 Drives)

The rough frequency distribution below is compiled from candidate reports and public preparation resources across recent React fresher interviews at Indian companies. These are estimated ranges, not measured figures:

Estimated ranges compiled from candidate reports and public preparation resources, not measured data.

Hooks dominate every round. If you do nothing else, master useState and useEffect cold, both conceptually and in live code.

Core Concepts: What Interviewers Actually Ask

JSX and the Virtual DOM

JSX is syntactic sugar over React.createElement(). Interviewers often ask you to rewrite a simple JSX block without JSX to check if you understand what's happening under the hood.

The virtual DOM is a lightweight in-memory representation of the real DOM. When state changes, React creates a new virtual DOM tree, diffs it against the previous one (reconciliation), and applies only the minimal set of real DOM changes. This is why React is faster than naive DOM manipulation.

Key follow-up question in 2026 interviews: "What is the diffing algorithm React uses?" Answer: React uses a heuristic O(n) algorithm (not O(n³)) by assuming components of different types produce different trees, and uses the key prop for list reconciliation.

Class Components vs Functional Components

In 2026, you will almost never write class components in a real job. But interviewers still ask about them to test foundational knowledge.

Props vs State

Props are read-only inputs passed from parent to child. State is mutable data owned by the component itself. A common trap question: "Can you modify props inside a component?", Answer: No. Props are immutable from the child's perspective. If you need to update them, lift state up.

Hooks Deep-Dive, The Section That Decides Your Offer

useState

const [count, setCount] = useState(0);

Pitfall interviewers test: stale closure problem. If you call setCount(count + 1) inside a setTimeout, count may be stale. Fix: use the functional updater form, setCount(prev => prev + 1).

useEffect

useEffect(() => {
  // side effect
  return () => {
    // cleanup
  };
}, [dependency]);

Dependency array rules:

• Empty [] → runs once on mount
• [value] → runs when value changes
• No array → runs after every render (almost never correct)

Cleanup matters: failing to clear subscriptions, timers, or event listeners causes memory leaks. This is a standard 2026 interview question at product companies.

useMemo and useCallback

useMemo memoizes a computed value. useCallback memoizes a function reference. Both accept a dependency array. Both are optimisations, use them when you can measure a real performance problem, not as default.

If asked "what's the difference?": useMemo returns the result of calling the function. useCallback returns the function itself.

useRef

Two use cases interviewers test:

1. Accessing DOM elements directly (e.g., focusing an input)
2. Storing a mutable value that does NOT trigger a re-render (e.g., interval ID)

Preparation Strategy for Freshers (30-Day Plan)

Build at least one deployable project (todo app is fine, but a weather app with API calls shows useEffect competency). Product companies will ask you to walk through your project live.

Also prepare system design basics, even fresher rounds at startups now include "how would you structure this React app?" type questions.

Practice Questions, React MCQs for Freshers