How to Prepare for PayU Interview 2026 — Complete Guide
Step-by-step preparation guide for PayU interviews. Covers what to study, how long to prepare, top resources, and 21 real questions reported by engineers who cleared the PayU process.
Step 1 — Understand what PayU actually tests
Based on 21 questions reported by engineers, PayU focuses on: DSA / Arrays, DSA / Hashmaps, JavaScript / Fundamentals, React / Concepts, React / Coding, JavaScript / Promises, React / Architecture, Frontend / Hierarchical Navigation, Frontend / Best Practices, Product Engineering, Java / Exceptions.
Step 2 — Study the right topics in order
- DSA / Arrays — 3 questions. Start here — highest weight in technical rounds.
- DSA / Hashmaps — 3 questions. Second priority after the first topic.
- JavaScript / Fundamentals — 3 questions. Cover once the first two topics are solid.
- React / Concepts — 1 questions. Cover once the first two topics are solid.
- React / Coding — 3 questions. Cover once the first two topics are solid.
- JavaScript / Promises — 2 questions. Cover once the first two topics are solid.
- React / Architecture — 2 questions. Cover once the first two topics are solid.
- Frontend / Hierarchical Navigation — 1 questions. Cover once the first two topics are solid.
- Frontend / Best Practices — 1 questions. Cover once the first two topics are solid.
- Product Engineering — 1 questions. Cover once the first two topics are solid.
- Java / Exceptions — 1 questions. Cover once the first two topics are solid.
Step 3 — Practice with real questions
These are the most upvoted questions engineers report being asked at PayU:
Predict the output of this code: console.log(1); setTimeout(() => console.log(2), 0); Promise.resolve().then(() => console.log(3)); console.log(4); Explain the event loop mechanism that determines this order.
Implement Promise.allSettled from scratch without using the native method. Then explain the difference between Promise.all, Promise.allSettled, Promise.any, and Promise.race — give a concrete payment flow example for when you would use each.
Explain the reconciliation algorithm in React. How does React decide which DOM nodes to update when state changes? What is the role of the key prop and what happens when you use an array index as a key versus a stable unique ID?
What will the following code output and why? const obj = { x: 10 }; const fn = () => console.log(this.x); obj.fn = fn; obj.fn(); Now rewrite fn as a regular function. How does the output change and what is the reason?
Implement a debounce function from scratch in JavaScript. Then explain where you would use debounce vs throttle in a payment checkout flow — for example on a search input, a "Pay Now" button, and a scroll event handler.
Step 4 — Analyse the job description
Paste the exact PayU JD into Stepkai's AI tool. It will extract the competencies being tested, score your current readiness, and generate a personalised day-by-day plan targeting your specific gaps — not a generic checklist.
Step 5 — Mock interview
Practice answering PayU questions with AI grading. Get instant feedback on depth, correctness, and communication before the real thing.
Start practising →