Interview experience
Infosys Interview Questions and Answers (2026)
Overview
Section titled “Overview”Infosys funnels most freshers through a single test (the IRT) into a standard Systems Engineer role, but a separate path - InfyTQ certification or the HackWithInfy coding contest - routes strong coders into the higher-paying Specialist Programmer/DSE track with a much harder interview.
Infosys interview process at a glance
Section titled “Infosys interview process at a glance”| Round | Duration | Focus Areas | Success Rate |
|---|---|---|---|
| IRT | 180 minutes | Aptitude, Reasoning, Coding | ~20% clear |
| Technical Interview | 30-50 minutes | Programming, Core Subjects, Projects (deeper for SP/DSE) | ~70% of IRT qualifiers |
| HR Interview | 20-30 minutes | Behavioral, Company Fit | ~90% of technical qualifiers |
IRT (Infosys Recruitment Test)
Section titled “IRT (Infosys Recruitment Test)”A 180-minute online test covering aptitude, reasoning, and a coding section. This is the steepest filter in the whole process - only around 1 in 5 candidates clear it, so time management across sections matters as much as raw accuracy.
Common questions
- Aptitude and reasoning - numerical ability, logical puzzles, data interpretation
- Coding section - 1-2 problems, typically array/string manipulation at an easy-to-medium level
- Basic programming-logic MCQs alongside the coding problems
Technical Interview (standard Systems Engineer track)
Section titled “Technical Interview (standard Systems Engineer track)”A 30-45 minute conversation mixing programming fundamentals, core CS subjects, and a detailed project walkthrough. Interviewers lean on “explain with an example” phrasing rather than pure theory recall.
Common questions
- C pointers, memory allocation (malloc/calloc), and array vs pointer differences
- Data structures - when to use an array vs a linked list, stack/queue basics
- DBMS - normalization (1NF/2NF/3NF), SQL query for the second-highest salary, joins
- OOPs - inheritance with an example, method overloading vs overriding
- A coding problem such as checking whether a string is a palindrome
Technical Interview (Specialist Programmer / DSE track)
Section titled “Technical Interview (Specialist Programmer / DSE track)”Reserved for candidates who clear HackWithInfy or score high on InfyTQ. Runs longer (45-50 minutes) and goes considerably deeper than the standard track.
Common questions
- JVM architecture and the Java collections framework hierarchy
- Time complexity of sorting algorithms; implement binary search
- Design a database schema for a given system (e.g. an e-commerce platform) and explain indexing
- Light system-design questions - how would you design a URL shortener? explain load balancing
- A DSA problem solved live on the coding portal in front of the interviewer (recent cycles require this)
Round-by-round breakdowns for both tracks are on the Infosys interview experience page.
HR Interview
Section titled “HR Interview”A closing 20-30 minute round on motivation and fit - the highest pass-through rate of the three stages, but still not a formality.
Common questions
- Tell me about yourself and why Infosys
- Are you willing to relocate to any Infosys location, including smaller campuses?
- Tell me about a project where you had to learn a new technology quickly to finish it
- Where do you see yourself in five years?
Sample answer frameworks for each of these are on the Infosys HR interview questions page.
Systems Engineer vs Specialist Programmer/DSE: two different bars
Section titled “Systems Engineer vs Specialist Programmer/DSE: two different bars”Most Infosys freshers go through the standard IRT-to-Systems-Engineer pipeline, where the technical interview tests fundamentals rather than advanced algorithms. A separate, smaller pool reaches Specialist Programmer (SP) or Digital Specialist Engineer (DSE) roles by clearing InfyTQ certification with a high score or performing well in HackWithInfy - Infosys’s own competitive-coding contest. That track’s coding bar (DP, graphs, trees, greedy problems, solved partly live under interviewer observation) and its technical interview (JVM internals, schema design, basic system design) sit well above what a standard Systems Engineer candidate needs to prepare for, and it pays meaningfully more. Know which track your score is routing you into before you decide how deep to go on DSA.
Common technical interview questions and answers
Section titled “Common technical interview questions and answers”Q: What is the difference between malloc and calloc in C?
Both allocate memory on the heap and return a void pointer that you cast to the required type, but malloc takes one argument, the total number of bytes, and leaves the memory uninitialised with whatever garbage was there before. calloc takes two arguments, the number of elements and the size of each, and zero-initialises every byte it hands back. So malloc(10 * sizeof(int)) and calloc(10, sizeof(int)) reserve the same amount of space, but only the calloc block is guaranteed to start as all zeros. Both return NULL when allocation fails, both must be released with free, and realloc is what you use to resize an existing block.
Q: What is the difference between an array and a pointer in C?
An array name is not a variable holding an address; it is the block of memory itself, and it decays to a pointer to its first element in most expressions, which is why arr[i] and pointer arithmetic behave alike. The differences show up elsewhere: sizeof on a locally declared array of 10 ints gives 40 bytes, while sizeof on a pointer gives the pointer size, typically 8 bytes. You also cannot reassign an array name the way you can reassign a pointer. This is why an array passed to a function arrives as a plain pointer and loses its length, so the length must be passed as a separate argument.
Q: When should you use an array versus a linked list?
Use an array when you need random access or cache-friendly iteration: indexing is O(1) because the address is computed arithmetically, and elements sit contiguously in memory. Use a linked list when you insert and delete frequently in the middle: given a node reference, unlinking is O(1), whereas an array insert or delete shifts the remaining elements in O(n). The trade-offs are the reverse for the other operations, since a linked list needs an O(n) traversal to reach the kth element and pays extra memory for each next pointer. In practice, dynamic arrays win for most workloads because of cache locality, and linked lists are chosen mainly when you need O(1) splicing, as in an LRU cache.
Q: How do you check whether a string is a palindrome?
Put one pointer at the first character and one at the last, compare them, and move both inward, returning false at the first mismatch and true if the pointers meet. That is O(n) time and O(1) space, and it beats reversing the string and comparing, which uses O(n) extra space. If the question asks for a case-insensitive, alphanumeric-only check, skip non-alphanumeric characters while moving each pointer and lowercase both characters before comparing. The recursive variant compares the outer pair and recurses on the substring inside, which is the same time bound but costs O(n) stack space.
Q: What is the difference between method overloading and method overriding?
Overloading means several methods in the same class share a name but differ in the number or types of their parameters; the compiler picks the right one at compile time, so it is static or compile-time polymorphism, and the return type alone is never enough to distinguish overloads. Overriding means a subclass provides a new implementation of an inherited method with the same name, parameter list, and a compatible return type; the JVM picks the implementation at runtime from the object’s actual class, so it is dynamic polymorphism. Overriding cannot reduce the visibility of the method or, in Java, add new checked exceptions, and static, private, and final methods cannot be overridden. Marking the subclass method with the Override annotation makes the compiler catch a mistyped signature that would otherwise silently become an overload.
Q: What are SQL joins, and what does an index actually do?
A join combines rows from two tables on a matching condition. INNER JOIN keeps only matching rows; LEFT JOIN keeps every row from the left table with NULLs where no match exists; RIGHT JOIN does the mirror image; FULL OUTER JOIN keeps unmatched rows from both sides. For example, SELECT s.name, d.dept_name FROM students s LEFT JOIN departments d ON s.dept_id = d.id; lists every student, including those with no department. An index is a separate sorted structure, usually a B-tree, over one or more columns, letting the database find matching rows in O(log n) instead of scanning the whole table. The cost is extra storage plus slower INSERT, UPDATE, and DELETE, since every write must also update the index, which is why you index the columns used in WHERE and JOIN conditions rather than every column.
Q: Explain the JVM architecture and the Java Collections hierarchy.
Java source compiles to platform-independent bytecode in a class file, which the JVM loads through the class loader subsystem, verifies, and then executes. Runtime memory splits into the heap for objects (divided into young and old generations for garbage collection), the method area for class metadata, and a per-thread stack holding frames plus a program counter. The execution engine interprets bytecode and promotes hot methods to native code through the JIT compiler. On the library side, the Collections framework hangs off two roots: Collection, with the List, Set, and Queue interfaces beneath it, and Map, which sits separately because it stores key-value pairs. ArrayList gives O(1) indexed access, LinkedList gives O(1) splicing, HashSet and HashMap give average O(1) lookup with no ordering, and TreeMap and TreeSet keep keys sorted with O(log n) operations.
Q: What are the time complexities of the common sorting algorithms, and how do you implement binary search?
Merge sort is O(n log n) in all cases and stable, but needs O(n) extra space. Quicksort averages O(n log n) with O(log n) stack space and sorts in place, but degrades to O(n squared) when pivots are chosen badly, which randomised or median-of-three pivots avoid. Heap sort is O(n log n) worst case in O(1) space but is not stable, while bubble, insertion, and selection sort are all O(n squared), with insertion sort a genuinely good choice for nearly sorted or very small inputs. Binary search then requires a sorted array: keep low and high bounds, compute mid as low + (high - low) / 2 to avoid integer overflow, return on a match, and otherwise move low to mid plus one or high to mid minus one depending on the comparison, halving the range each step for O(log n) time.
Frequently asked questions about Infosys interviews
Section titled “Frequently asked questions about Infosys interviews”What is the Infosys interview process for freshers?
Infosys hires freshers mainly through the InfyTQ / Infosys Recruitment Test (IRT): 1. IRT (180 minutes) - Aptitude, Reasoning, and Coding sections, with roughly 20% of candidates clearing it. 2. Technical Interview (30-50 minutes) - programming, core CS subjects, and project discussion, clearing around 70% of IRT qualifiers. 3. HR Interview (20-30 minutes) - behavioral fit and company motivation, clearing around 90% of technical qualifiers.
What questions are asked in Infosys interviews?
Infosys interviews cover aptitude and reasoning in the IRT, basic-to-medium coding problems and core subjects (OOP, DBMS, OS, networking) in the Technical round, and standard HR questions on relocation, career goals, and motivation for joining Infosys in the final round. Candidates on the Specialist Programmer/Digital Specialist Engineer track get noticeably deeper questions - JVM internals, system design basics, database schema design.
How many rounds are there in the Infosys interview?
Infosys typically runs 3 stages for freshers: the IRT (aptitude + reasoning + coding), a Technical Interview, and an HR Interview. Candidates who clear HackWithInfy or score high on InfyTQ certification get routed into the Specialist Programmer (SP) / Digital Specialist Engineer (DSE) track instead, which adds a harder, longer coding round.
What is the difference between Infosys Systems Engineer and Specialist Programmer (SP) / Digital Specialist Engineer (DSE)?
Systems Engineer is the standard fresher track via the IRT. SP and DSE are separate, higher-paying tracks reached through Infosys’s InfyTQ certification (a year-round learning-and-certification program) or HackWithInfy (an annual competitive coding contest) - both test 2-3 coding problems (medium-to-hard, DP/graphs/trees/greedy) in a much longer window, and in recent cycles candidates have had to solve at least one problem live in front of the interviewer.
How should I prepare for Infosys interviews?
For Infosys, practice aptitude and reasoning alongside basic-to-medium DSA for the IRT, revise core CS fundamentals (OOP, DBMS, OS, networking) for the Technical round, and prepare clear answers on relocation flexibility and why you want to join Infosys for the HR round. If you’re aiming for SP/DSE, prepare HackWithInfy-level DSA (DP, graphs, trees) since that track’s coding bar is much higher than the standard IRT.
How selective is Infosys hiring for freshers?
Selective at the first stage: roughly 20% of IRT candidates clear it. From there the funnel opens up - about 70% of IRT qualifiers clear the Technical Interview, and about 90% of those clear HR, for an overall selection rate of roughly 12-15% of total applicants.