Home/Prepare/TCS

How to Prepare for TCS Interview 2026 — Complete Guide

Published July 22, 2026 · Updated July 22, 2026

Step-by-step preparation guide for TCS interviews. Covers what to study, how long to prepare, top resources, and 167 real questions reported by engineers who cleared the TCS process.

Step 1 — Understand what TCS actually tests

Based on 167 questions reported by engineers, TCS focuses on: Domain, System Design, Behavioral, DSA / Arrays, React / Strict Mode, React / Browser Compatibility, React / Cross-browser, React / State Management, React / Migration, Node.js / Performance, Node.js / Streams, Node.js / Error Handling, SQL / Query Planning, SQL / Indexing, SQL / MySQL, SQL / Advanced SQL, SQL / Maintenance, SQL / Database Architecture, Java / Spring Transactions, Java / Connection Pool, Java / Concurrency, Java / Performance, Java / Spring Async, Java / Design Patterns, Python / Django ORM, DevOps / Docker, Security / Information Disclosure, Security / Cryptography, Behavioral / Technical Debt, DSA / Stack, DSA / Sliding Window, React / Code Splitting, React / Hooks, Java / Spring Boot, Java / Threading, Java / Optional, Java / Exception Handling, Java / Memory, Java / Core Java, Java / Spring AOP, Java / Hibernate, Java / Generics, Python / Deployment, Python / Core Python, SQL / Window Functions, SQL / Set Operations, Security / CORS, TypeScript / Migration, Java / API Versioning, Java / Spring Boot Internals, Java / Scheduling, Java / Spring Security, Java / Spring Core, Java / Spring MVC, Java / Spring Scopes, Java / Testing, DSA / String, DSA / Bit Manipulation, Behavioral / Project Management, Behavioral / Agile, React / Keys, React / Framework Comparison, Node.js / Middleware, Node.js / Clustering, SQL / MySQL Query Analysis, SQL / Data Types, React / Mobile Debugging, Behavioral / Team Collaboration, Java / Migration, DevOps / Debugging, Performance / N+1, Redis / Operations, React / Routing, React / Best Practices, React / State, React / Modules, Java / Streams, Java / Functional Programming, Java / JVM, Node.js / Modules, Node.js / Security, Python / Advanced Python, Python / Flask, Python / Security, Python / OOP, DSA / Strings, DSA / Sorting, Security / OWASP, Security / Access Control, Security / Authentication, Security / Transport Security, SQL / Joins, SQL / Transactions, SQL / Data Cleaning, SQL / Basics, MongoDB / Use Cases, MongoDB / Aggregation, MongoDB / Data Modeling, TypeScript / Types, TypeScript / Best Practices, Security / Auth, Architecture / Design Principles, React / Forms, React / Context, React / Error Handling, Java / Spring Cloud, Java / Spring Batch, Java / Database, Web / Real-time, Behavioral / Business Analysis, Business Analysis / Requirements, Business Analysis / Requirements Gathering, Business Analysis / Analysis, Business Analysis / Documentation, Web / Security, React / DOM, Security / SQL Injection, Security / Web Security, DSA / Graph, DSA / Data Structures, Java / Modern Java, Java / Collections, Architecture / REST API.

Topics: 123
Questions reported: 167
Engineers interviewed: 4785

Step 2 — Study the right topics in order

  1. Domain — 7 questions. Start here — highest weight in technical rounds.
  2. System Design — 2 questions. Second priority after the first topic.
  3. Behavioral — 1 questions. Cover once the first two topics are solid.
  4. DSA / Arrays — 2 questions. Cover once the first two topics are solid.
  5. React / Strict Mode — 1 questions. Cover once the first two topics are solid.
  6. React / Browser Compatibility — 1 questions. Cover once the first two topics are solid.
  7. React / Cross-browser — 1 questions. Cover once the first two topics are solid.
  8. React / State Management — 3 questions. Cover once the first two topics are solid.
  9. React / Migration — 1 questions. Cover once the first two topics are solid.
  10. Node.js / Performance — 2 questions. Cover once the first two topics are solid.
  11. Node.js / Streams — 1 questions. Cover once the first two topics are solid.
  12. Node.js / Error Handling — 2 questions. Cover once the first two topics are solid.
  13. SQL / Query Planning — 2 questions. Cover once the first two topics are solid.
  14. SQL / Indexing — 3 questions. Cover once the first two topics are solid.
  15. SQL / MySQL — 1 questions. Cover once the first two topics are solid.
  16. SQL / Advanced SQL — 1 questions. Cover once the first two topics are solid.
  17. SQL / Maintenance — 1 questions. Cover once the first two topics are solid.
  18. SQL / Database Architecture — 1 questions. Cover once the first two topics are solid.
  19. Java / Spring Transactions — 2 questions. Cover once the first two topics are solid.
  20. Java / Connection Pool — 1 questions. Cover once the first two topics are solid.
  21. Java / Concurrency — 1 questions. Cover once the first two topics are solid.
  22. Java / Performance — 2 questions. Cover once the first two topics are solid.
  23. Java / Spring Async — 1 questions. Cover once the first two topics are solid.
  24. Java / Design Patterns — 1 questions. Cover once the first two topics are solid.
  25. Python / Django ORM — 1 questions. Cover once the first two topics are solid.
  26. DevOps / Docker — 3 questions. Cover once the first two topics are solid.
  27. Security / Information Disclosure — 1 questions. Cover once the first two topics are solid.
  28. Security / Cryptography — 2 questions. Cover once the first two topics are solid.
  29. Behavioral / Technical Debt — 1 questions. Cover once the first two topics are solid.
  30. DSA / Stack — 2 questions. Cover once the first two topics are solid.
  31. DSA / Sliding Window — 1 questions. Cover once the first two topics are solid.
  32. React / Code Splitting — 2 questions. Cover once the first two topics are solid.
  33. React / Hooks — 4 questions. Cover once the first two topics are solid.
  34. Java / Spring Boot — 7 questions. Cover once the first two topics are solid.
  35. Java / Threading — 1 questions. Cover once the first two topics are solid.
  36. Java / Optional — 1 questions. Cover once the first two topics are solid.
  37. Java / Exception Handling — 3 questions. Cover once the first two topics are solid.
  38. Java / Memory — 2 questions. Cover once the first two topics are solid.
  39. Java / Core Java — 2 questions. Cover once the first two topics are solid.
  40. Java / Spring AOP — 1 questions. Cover once the first two topics are solid.
  41. Java / Hibernate — 1 questions. Cover once the first two topics are solid.
  42. Java / Generics — 1 questions. Cover once the first two topics are solid.
  43. Python / Deployment — 1 questions. Cover once the first two topics are solid.
  44. Python / Core Python — 3 questions. Cover once the first two topics are solid.
  45. SQL / Window Functions — 4 questions. Cover once the first two topics are solid.
  46. SQL / Set Operations — 1 questions. Cover once the first two topics are solid.
  47. Security / CORS — 1 questions. Cover once the first two topics are solid.
  48. TypeScript / Migration — 1 questions. Cover once the first two topics are solid.
  49. Java / API Versioning — 1 questions. Cover once the first two topics are solid.
  50. Java / Spring Boot Internals — 1 questions. Cover once the first two topics are solid.
  51. Java / Scheduling — 1 questions. Cover once the first two topics are solid.
  52. Java / Spring Security — 2 questions. Cover once the first two topics are solid.
  53. Java / Spring Core — 1 questions. Cover once the first two topics are solid.
  54. Java / Spring MVC — 1 questions. Cover once the first two topics are solid.
  55. Java / Spring Scopes — 1 questions. Cover once the first two topics are solid.
  56. Java / Testing — 1 questions. Cover once the first two topics are solid.
  57. DSA / String — 1 questions. Cover once the first two topics are solid.
  58. DSA / Bit Manipulation — 1 questions. Cover once the first two topics are solid.
  59. Behavioral / Project Management — 1 questions. Cover once the first two topics are solid.
  60. Behavioral / Agile — 1 questions. Cover once the first two topics are solid.
  61. React / Keys — 1 questions. Cover once the first two topics are solid.
  62. React / Framework Comparison — 1 questions. Cover once the first two topics are solid.
  63. Node.js / Middleware — 1 questions. Cover once the first two topics are solid.
  64. Node.js / Clustering — 1 questions. Cover once the first two topics are solid.
  65. SQL / MySQL Query Analysis — 1 questions. Cover once the first two topics are solid.
  66. SQL / Data Types — 1 questions. Cover once the first two topics are solid.
  67. React / Mobile Debugging — 1 questions. Cover once the first two topics are solid.
  68. Behavioral / Team Collaboration — 1 questions. Cover once the first two topics are solid.
  69. Java / Migration — 1 questions. Cover once the first two topics are solid.
  70. DevOps / Debugging — 1 questions. Cover once the first two topics are solid.
  71. Performance / N+1 — 1 questions. Cover once the first two topics are solid.
  72. Redis / Operations — 1 questions. Cover once the first two topics are solid.
  73. React / Routing — 1 questions. Cover once the first two topics are solid.
  74. React / Best Practices — 1 questions. Cover once the first two topics are solid.
  75. React / State — 1 questions. Cover once the first two topics are solid.
  76. React / Modules — 1 questions. Cover once the first two topics are solid.
  77. Java / Streams — 1 questions. Cover once the first two topics are solid.
  78. Java / Functional Programming — 1 questions. Cover once the first two topics are solid.
  79. Java / JVM — 1 questions. Cover once the first two topics are solid.
  80. Node.js / Modules — 1 questions. Cover once the first two topics are solid.
  81. Node.js / Security — 1 questions. Cover once the first two topics are solid.
  82. Python / Advanced Python — 1 questions. Cover once the first two topics are solid.
  83. Python / Flask — 1 questions. Cover once the first two topics are solid.
  84. Python / Security — 1 questions. Cover once the first two topics are solid.
  85. Python / OOP — 1 questions. Cover once the first two topics are solid.
  86. DSA / Strings — 2 questions. Cover once the first two topics are solid.
  87. DSA / Sorting — 2 questions. Cover once the first two topics are solid.
  88. Security / OWASP — 1 questions. Cover once the first two topics are solid.
  89. Security / Access Control — 1 questions. Cover once the first two topics are solid.
  90. Security / Authentication — 1 questions. Cover once the first two topics are solid.
  91. Security / Transport Security — 1 questions. Cover once the first two topics are solid.
  92. SQL / Joins — 1 questions. Cover once the first two topics are solid.
  93. SQL / Transactions — 1 questions. Cover once the first two topics are solid.
  94. SQL / Data Cleaning — 1 questions. Cover once the first two topics are solid.
  95. SQL / Basics — 1 questions. Cover once the first two topics are solid.
  96. MongoDB / Use Cases — 1 questions. Cover once the first two topics are solid.
  97. MongoDB / Aggregation — 1 questions. Cover once the first two topics are solid.
  98. MongoDB / Data Modeling — 1 questions. Cover once the first two topics are solid.
  99. TypeScript / Types — 1 questions. Cover once the first two topics are solid.
  100. TypeScript / Best Practices — 1 questions. Cover once the first two topics are solid.
  101. Security / Auth — 1 questions. Cover once the first two topics are solid.
  102. Architecture / Design Principles — 1 questions. Cover once the first two topics are solid.
  103. React / Forms — 1 questions. Cover once the first two topics are solid.
  104. React / Context — 1 questions. Cover once the first two topics are solid.
  105. React / Error Handling — 1 questions. Cover once the first two topics are solid.
  106. Java / Spring Cloud — 1 questions. Cover once the first two topics are solid.
  107. Java / Spring Batch — 1 questions. Cover once the first two topics are solid.
  108. Java / Database — 1 questions. Cover once the first two topics are solid.
  109. Web / Real-time — 1 questions. Cover once the first two topics are solid.
  110. Behavioral / Business Analysis — 1 questions. Cover once the first two topics are solid.
  111. Business Analysis / Requirements — 2 questions. Cover once the first two topics are solid.
  112. Business Analysis / Requirements Gathering — 1 questions. Cover once the first two topics are solid.
  113. Business Analysis / Analysis — 1 questions. Cover once the first two topics are solid.
  114. Business Analysis / Documentation — 1 questions. Cover once the first two topics are solid.
  115. Web / Security — 1 questions. Cover once the first two topics are solid.
  116. React / DOM — 1 questions. Cover once the first two topics are solid.
  117. Security / SQL Injection — 1 questions. Cover once the first two topics are solid.
  118. Security / Web Security — 1 questions. Cover once the first two topics are solid.
  119. DSA / Graph — 1 questions. Cover once the first two topics are solid.
  120. DSA / Data Structures — 1 questions. Cover once the first two topics are solid.
  121. Java / Modern Java — 1 questions. Cover once the first two topics are solid.
  122. Java / Collections — 1 questions. Cover once the first two topics are solid.
  123. Architecture / REST API — 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 TCS:

TCS Medium Technical round JavaSpring Boot

What are the SOLID principles? Explain each with a real-world Java example. Then describe a scenario where rigidly following SOLID leads to over-engineering, and how you balance pragmatism with good design.

↑ 93 upvotes · 36 engineers asked this · SDE2
TCS Easy Technical round 1-3 years

Implement a function that checks if a string of brackets is valid. Brackets: (), [], {}. Must handle nested brackets.

↑ 84 upvotes · 32 engineers asked this · SDE1
TCS Medium Technical round 2-4 years

A developer puts async code inside useEffect by returning an async arrow function: useEffect(() => async () => {...}). Why is this wrong?

↑ 84 upvotes · 22 engineers asked this · SDE2
TCS Medium Screening round 3-6 years

Explain service discovery in microservices. How does Eureka work with Spring Cloud?

↑ 84 upvotes · 32 engineers asked this · SDE2
TCS Medium Technical round 2-5 years

Your PostgreSQL query plan shows 'Seq Scan' on a small 1000-row table despite having an index. Why might Postgres choose not to use the index?

↑ 83 upvotes · 41 engineers asked this · SDE2

Step 4 — Analyse the job description

Paste the exact TCS 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.

Analyse my JD →

Step 5 — Mock interview

Practice answering TCS questions with AI grading. Get instant feedback on depth, correctness, and communication before the real thing.

Start practising →

All TCS questions by technology

TCS Java TCS Spring Boot

Preparation guides for other companies

How to prepare for Amazon How to prepare for Google How to prepare for Microsoft How to prepare for Flipkart How to prepare for Swiggy How to prepare for Meta How to prepare for Apple How to prepare for Netflix How to prepare for Uber How to prepare for Airbnb

Frequently asked questions

How long does it take to prepare for TCS interview?
For experienced engineers, 2–4 weeks of focused preparation covering Domain, System Design, Behavioral, DSA / Arrays, React / Strict Mode, React / Browser Compatibility, React / Cross-browser, React / State Management, React / Migration, Node.js / Performance, Node.js / Streams, Node.js / Error Handling, SQL / Query Planning, SQL / Indexing, SQL / MySQL, SQL / Advanced SQL, SQL / Maintenance, SQL / Database Architecture, Java / Spring Transactions, Java / Connection Pool, Java / Concurrency, Java / Performance, Java / Spring Async, Java / Design Patterns, Python / Django ORM, DevOps / Docker, Security / Information Disclosure, Security / Cryptography, Behavioral / Technical Debt, DSA / Stack, DSA / Sliding Window, React / Code Splitting, React / Hooks, Java / Spring Boot, Java / Threading, Java / Optional, Java / Exception Handling, Java / Memory, Java / Core Java, Java / Spring AOP, Java / Hibernate, Java / Generics, Python / Deployment, Python / Core Python, SQL / Window Functions, SQL / Set Operations, Security / CORS, TypeScript / Migration, Java / API Versioning, Java / Spring Boot Internals, Java / Scheduling, Java / Spring Security, Java / Spring Core, Java / Spring MVC, Java / Spring Scopes, Java / Testing, DSA / String, DSA / Bit Manipulation, Behavioral / Project Management, Behavioral / Agile, React / Keys, React / Framework Comparison, Node.js / Middleware, Node.js / Clustering, SQL / MySQL Query Analysis, SQL / Data Types, React / Mobile Debugging, Behavioral / Team Collaboration, Java / Migration, DevOps / Debugging, Performance / N+1, Redis / Operations, React / Routing, React / Best Practices, React / State, React / Modules, Java / Streams, Java / Functional Programming, Java / JVM, Node.js / Modules, Node.js / Security, Python / Advanced Python, Python / Flask, Python / Security, Python / OOP, DSA / Strings, DSA / Sorting, Security / OWASP, Security / Access Control, Security / Authentication, Security / Transport Security, SQL / Joins, SQL / Transactions, SQL / Data Cleaning, SQL / Basics, MongoDB / Use Cases, MongoDB / Aggregation, MongoDB / Data Modeling, TypeScript / Types, TypeScript / Best Practices, Security / Auth, Architecture / Design Principles, React / Forms, React / Context, React / Error Handling, Java / Spring Cloud, Java / Spring Batch, Java / Database, Web / Real-time, Behavioral / Business Analysis, Business Analysis / Requirements, Business Analysis / Requirements Gathering, Business Analysis / Analysis, Business Analysis / Documentation, Web / Security, React / DOM, Security / SQL Injection, Security / Web Security, DSA / Graph, DSA / Data Structures, Java / Modern Java, Java / Collections, Architecture / REST API is typically sufficient for TCS.
What topics should I study for TCS interview?
TCS interview questions cover Domain, System Design, Behavioral, DSA / Arrays, React / Strict Mode, React / Browser Compatibility, React / Cross-browser, React / State Management, React / Migration, Node.js / Performance, Node.js / Streams, Node.js / Error Handling, SQL / Query Planning, SQL / Indexing, SQL / MySQL, SQL / Advanced SQL, SQL / Maintenance, SQL / Database Architecture, Java / Spring Transactions, Java / Connection Pool, Java / Concurrency, Java / Performance, Java / Spring Async, Java / Design Patterns, Python / Django ORM, DevOps / Docker, Security / Information Disclosure, Security / Cryptography, Behavioral / Technical Debt, DSA / Stack, DSA / Sliding Window, React / Code Splitting, React / Hooks, Java / Spring Boot, Java / Threading, Java / Optional, Java / Exception Handling, Java / Memory, Java / Core Java, Java / Spring AOP, Java / Hibernate, Java / Generics, Python / Deployment, Python / Core Python, SQL / Window Functions, SQL / Set Operations, Security / CORS, TypeScript / Migration, Java / API Versioning, Java / Spring Boot Internals, Java / Scheduling, Java / Spring Security, Java / Spring Core, Java / Spring MVC, Java / Spring Scopes, Java / Testing, DSA / String, DSA / Bit Manipulation, Behavioral / Project Management, Behavioral / Agile, React / Keys, React / Framework Comparison, Node.js / Middleware, Node.js / Clustering, SQL / MySQL Query Analysis, SQL / Data Types, React / Mobile Debugging, Behavioral / Team Collaboration, Java / Migration, DevOps / Debugging, Performance / N+1, Redis / Operations, React / Routing, React / Best Practices, React / State, React / Modules, Java / Streams, Java / Functional Programming, Java / JVM, Node.js / Modules, Node.js / Security, Python / Advanced Python, Python / Flask, Python / Security, Python / OOP, DSA / Strings, DSA / Sorting, Security / OWASP, Security / Access Control, Security / Authentication, Security / Transport Security, SQL / Joins, SQL / Transactions, SQL / Data Cleaning, SQL / Basics, MongoDB / Use Cases, MongoDB / Aggregation, MongoDB / Data Modeling, TypeScript / Types, TypeScript / Best Practices, Security / Auth, Architecture / Design Principles, React / Forms, React / Context, React / Error Handling, Java / Spring Cloud, Java / Spring Batch, Java / Database, Web / Real-time, Behavioral / Business Analysis, Business Analysis / Requirements, Business Analysis / Requirements Gathering, Business Analysis / Analysis, Business Analysis / Documentation, Web / Security, React / DOM, Security / SQL Injection, Security / Web Security, DSA / Graph, DSA / Data Structures, Java / Modern Java, Java / Collections, Architecture / REST API. The most upvoted topics from 167 real questions are: Domain, System Design, Behavioral.
Is TCS interview hard?
Difficulty levels range from Medium to Easy to Hard. Most questions are Medium. Preparation with real questions from engineers who cleared the loop makes a significant difference.