Previous-year papers are the closest practice you can get to GATE CSE, because they are real papers. This page shows where they are officially published with answer keys, the current pattern to read them against and how to use them section by section, then gives 12 original practice questions with worked solutions. For structured practice across the same ten sections, see the Myndaq GATE CS course.
The GATE CSE paper pattern
As published by IIT Madras on the official pattern page and brochure, read on 16 September 2026:
- 65 questions, 100 marks, 3 hours - computer-based, in a forenoon (9:30 AM to 12:30 PM) or afternoon (2:30 PM to 5:30 PM) session
- General Aptitude - 10 questions for 15 marks
- Subject component - 55 questions for 85 marks; in the CS paper, Engineering Mathematics carries 13 of those 85 marks
- Question types - 1- or 2-mark MCQ (four options, one correct), MSQ (four options, one or more correct) and NAT (a signed number typed on a virtual keypad, to the decimal places the question states)
- Marking - a wrong 1-mark MCQ loses 1/3 mark and a wrong 2-mark MCQ 2/3; MSQ and NAT have no negative marks, and no question earns partial marks
- Calculator - only the on-screen virtual calculator
The attempt-or-skip arithmetic is in the GATE exam pattern and marking scheme guide, and NAT entry habits in NAT and virtual calculator strategy.
Where the official previous-year papers and answer keys are
- Official GATE Downloads page - the brochure points here for papers from 2007 to 2026; the page has a bulk download of them plus year-wise papers and answer keys for 2021 to 2026.
- GATE 2026 page at IIT Guwahati - lists CS-1 (forenoon) and CS-2 (afternoon), each with its own master question paper and answer key. Each key follows its own paper's question order, so never mix them.
This page reproduces no official question. Two cautions:
- Check old questions against the current syllabus. IIT Madras has published revised syllabi; if a question's topic is not in the official CS syllabus PDF, set it aside.
- Treat the official key as the reference for any unofficial solution.
How to use previous-year questions, section by section
Work in two passes: untimed by section until your method is reliable, then full three-hour papers, logging every lost mark by section, format and reason.
- Engineering Mathematics - track discrete mathematics apart from linear algebra, calculus and probability.
- Digital Logic - redo minimisations by hand and check number representations bit by bit.
- Computer Organization and Architecture - in pipelining and cache numericals, write units at every step and round only at the end.
- Programming and Data Structures - trace C code on paper and commit to an answer before checking.
- Algorithms - name the design technique and write the recurrence before solving.
- Theory of Computation - write why each language is or is not regular; judge every MSQ option alone.
- Compiler Design - rebuild FIRST and FOLLOW sets and parsing tables instead of reading solutions.
- Operating System - draw the Gantt chart or frame table every time.
- Databases - drill attribute closures and normal-form checks until they are mechanical.
- Computer Networks - practise subnetting and delay numericals; list formulas you got wrong.
Practice questions in the GATE style
The 12 questions below are original practice questions written by Myndaq in the official GATE style, not official past-paper questions.
Q1 - Engineering Mathematics, NAT, 1 mark
Two fair six-sided dice are rolled. Given that at least one die shows a 3, what is the probability that the sum is 8? Round off to two decimal places.
Answer: 0.18. 11 of the 36 outcomes (36 − 25) show at least one 3, and only (3, 5) and (5, 3) of those sum to 8, giving 2/11 = 0.1818..., or 0.18.
Q2 - Engineering Mathematics, MCQ, 2 marks
A is the 2 × 2 matrix with rows (2, 1) and (1, 2). The sum of the eigenvalues of A² is:
- (A) 8
- (B) 10
- (C) 16
- (D) 20
Answer: (B). A has trace 4 and determinant 3, so its eigenvalues are 1 and 3. The eigenvalues of A² are their squares, 1 and 9, which sum to 10.
Q3 - Digital Logic, MSQ, 1 mark
F(A, B, C) = Σm(1, 3, 5, 7). Which are correct?
- (A) F = C
- (B) F does not depend on A
- (C) F has four prime implicants
- (D) F = A′C + AC
Answer: (A), (B) and (D). Minterms 001, 011, 101 and 111 are exactly the rows with C = 1, so F = C, independent of A and B. C is the only prime implicant, so (C) is false, and A′C + AC = C.
Q4 - Computer Organization and Architecture, NAT, 2 marks
A 5-stage pipeline has stage delays of 150, 120, 160, 140 and 130 ps, and each pipeline register adds 10 ps. With no stalls, find the time in nanoseconds to execute 100 instructions, rounded off to two decimal places.
Answer: 17.68. The clock period is the slowest stage plus the register delay, 160 + 10 = 170 ps. Five stages and 100 instructions need 5 + 100 − 1 = 104 cycles, so the time is 104 × 170 = 17,680 ps = 17.68 ns.
Q5 - Programming and Data Structures, MCQ, 1 mark
Consider the C function int f(int n) { if (n <= 1) return 1; return f(n - 1) + 2 * f(n - 2); }. The value returned by f(5) is:
- (A) 11
- (B) 21
- (C) 23
- (D) 43
Answer: (B). f(0) = f(1) = 1. Then f(2) = 1 + 2 × 1 = 3, f(3) = 3 + 2 × 1 = 5, f(4) = 5 + 2 × 3 = 11 and f(5) = 11 + 2 × 5 = 21.
Q6 - Algorithms, MCQ, 2 marks
The solution of T(n) = 4T(n/2) + n² log n is:
- (A) Θ(n²)
- (B) Θ(n² log n)
- (C) Θ(n² log² n)
- (D) Θ(n³)
Answer: (C). With a = 4 and b = 2, n to the power log₂4 is n², and the extra work is n² times log n, so the extended master theorem gives Θ(n² log² n).
Q7 - Algorithms, NAT, 2 marks
An undirected graph on vertices A, B, C, D and E has edges A-B (4), A-C (1), B-C (2), B-D (5), C-D (8), C-E (10) and D-E (3). What is the weight of its minimum spanning tree?
Answer: 11. Kruskal's algorithm accepts A-C (1), B-C (2) and D-E (3), rejects A-B (4) as it closes a cycle, and accepts B-D (5) to join the components: 1 + 2 + 3 + 5 = 11.
Q8 - Theory of Computation, MSQ, 2 marks
Which languages are regular?
- (A)
{ a^n b^n : n >= 0 } - (B) strings over {a, b} in which the number of a's is divisible by 3
- (C)
{ a^n b^m : n, m >= 0 } - (D)
{ ww : w in {a,b}* }
Answer: (B) and (C). (B) needs only a three-state DFA counting a's modulo 3, and (C) is a*b*. (A) fails the pumping lemma, and (D) is not even context-free.
Q9 - Compiler Design, NAT, 1 mark
How many tokens does a C lexical analyser produce for the statement if (x >= 10) y = x * 2;?
Answer: 12. The tokens are if, (, x, >=, 10, ), y, =, x, the multiplication operator, 2 and the semicolon. The operator >= is one token, not two.
Q10 - Operating System, NAT, 2 marks
A process has 3 initially empty frames. For the reference string 1, 2, 3, 4, 1, 2, 5, 1, 2, 3, 4, 5, how many page faults occur under LRU page replacement?
Answer: 10. The first three references fill the frames (3 faults). Evicting the least recently used page each time, 4 evicts 1, 1 evicts 2, 2 evicts 3 and 5 evicts 4 (4 faults). The next 1 and 2 are hits. Then 3 evicts 5, 4 evicts 1 and 5 evicts 2 (3 faults), for 10 in total.
Q11 - Databases, MCQ, 2 marks
Relation R(A, B, C, D, E) has the functional dependencies A → B, B → C and CD → E. Which statement is correct?
- (A) Only key AD; 1NF but not 2NF
- (B) Only key AD; 2NF but not 3NF
- (C) Keys AD and AC; 3NF
- (D) Key ABD; BCNF
Answer: (A). A and D appear on no right-hand side, so every key contains both, and the closure of AD is ABCDE (A gives B, B gives C, CD gives E). So AD is the only candidate key and ABD is not minimal. A → B is a partial dependency of the non-prime B on the key, violating 2NF.
Q12 - Computer Networks, MSQ, 2 marks
A host has the address 192.168.10.77/27. Which are correct?
- (A) The network address is 192.168.10.64
- (B) The broadcast address is 192.168.10.95
- (C) The subnet has 30 usable host addresses
- (D) 192.168.10.100 is in the same subnet
Answer: (A), (B) and (C). A /27 mask leaves 5 host bits, so blocks have 32 addresses and this one runs from .64 (network) to .95 (broadcast), with 32 − 2 = 30 usable hosts. Address .100 falls in the next block, .96 to .127.
Quick answers
Where can I download GATE CSE previous year papers officially?
From the official GATE Downloads page (year-wise papers and keys, plus a bulk download for 2007 to 2026) and from past organising-institute sites such as IIT Guwahati for 2026.
Are the practice questions on this page from real GATE papers?
No. They are original practice questions written by Myndaq in the GATE style. For real questions, use the official papers linked below.
Is there negative marking on MSQ and NAT questions?
No. Only wrong MCQ answers lose marks, 1/3 for a 1-mark MCQ and 2/3 for a 2-mark MCQ, and no question gets partial marks.
Are older GATE CS papers still useful after a syllabus revision?
Yes, once you check each question's topic against the current official CS syllabus PDF, since IIT Madras has published revised syllabi.
