IISER 2025 Question Paper & Answer Key; Download PDF
IISER Aptitude Test (IAT) 2025 was conducted on May 25, 2025, for admission to BS-MS, BS, and BTech programmes offered by IISERs and participating institutes. Conducted by IISER Tirupati, the computer-based test featured 60 questions from Physics, Chemistry, Mathematics, and Biology for a total of 240 marks.
IISER 2025 Question Paper & Answer Key PDF Download
| Question Paper PDF | Answer Key PDF |
|---|---|
IISER 2025 IAT Question Paper and Answer Key PDF (May 25, 2025) |
Download PDF |
IISER Aptitude Test consisted of questions from four subjects: Physics, Chemistry, Mathematics, and Biology. Unlike many entrance exams, all candidates were required to attempt questions from every subject regardless of their Class 12 stream.
IISER Shifts Timings
At 2025 was held in a single shift across all examination centres on May 25, 2025. The exam was conducted during the morning session and followed the same schedule for candidates nationwide.
| Particulars | Details |
|---|---|
| Shift | Single Shift |
| Exam Timing | 9:00 AM to 12:00 PM |
| Duration | 3 Hours |
IISER 2025 Exam Pattern
IISER Aptitude Test (IAT) 2025 was conducted in Computer-Based Test (CBT) mode and assessed candidates on Physics, Chemistry, Mathematics, and Biology. All candidates could attempt questions from all four subjects irrespective of their Class 12 stream.
| Particulars | Details |
|---|---|
| Exam Name | IISER Aptitude Test (IAT) 2025 |
| Mode of Examination | Computer-Based Test (CBT) |
| Duration | 180 Minutes (3 Hours) |
| Question Type | Multiple Choice Questions (MCQs) |
| Total Questions | 60 |
| Subjects | Physics, Chemistry, Mathematics, Biology |
| Questions per Subject | 15 |
| Maximum Marks | 240 |
| Medium | English |
| Marking Scheme | +4 for Correct Answer |
| Negative Marking | -1 for Incorrect Answer |
| Unanswered Questions | 0 Marks |
IISER 2025 Subject-Wise Question Distribution
| Subject | Questions | Maximum Marks |
|---|---|---|
| Physics | 15 | 60 |
| Chemistry | 15 | 60 |
| Mathematics | 15 | 60 |
| Biology | 15 | 60 |
| Total | 60 | 240 |
IISER 2025 Detailed Paper Analysis
IISER 2025 based on student feedback and expert reviews, was considered moderate in difficulty overall. The paper focused heavily on conceptual understanding rather than direct formula-based questions.
IISER 2025 Physics
IISER 2025 Physics Questions from Mechanics, Modern Physics, Electrodynamics, and Thermodynamics dominated the paper. Numerical applications and multi-concept problems required strong analytical thinking.
IISER 2025 Chemistry:
IISER 2025 Chemistry Physical Chemistry carried significant weightage, while Organic Chemistry focused on reaction mechanisms and conceptual understanding. Inorganic Chemistry was largely NCERT-based.
IISER 2025 Mathematics:
IISER 2025 Mathematics Calculus, Algebra, Coordinate Geometry, and Probability accounted for a major share of questions. Several questions required lengthy calculations and advanced conceptual application.
IISER 2025 Biology:
IISER 2025 Biology Questions were mainly based on Genetics, Ecology, Human Physiology, Biotechnology, and Cell Biology. Students with strong NCERT preparation found the section manageable.
IISER 2025 Subject-Wise Difficulty Analysis
| Subject | Difficulty Level | Important Topics |
|---|---|---|
| Physics | Moderate-Difficult | Mechanics, Electrodynamics, Modern Physics |
| Chemistry | Moderate | Physical Chemistry, Organic Reactions |
| Mathematics | Difficult | Calculus, Algebra, Probability |
| Biology | Moderate | Genetics, Ecology, Physiology |
| Overall | Moderate | Concept-based questions |
Why Solve IISER 2025 Question Paper?
Solving IISER 2025 question paper helps candidates understand the exam pattern, improve speed and accuracy, and assess their preparation level before the actual test.
- Understand the Exam Pattern and question difficulty level.
- Identify Important Topics frequently asked in the IAT.
- Improve Time Management for the 180-minute exam.
- Boost Accuracy and Confidence through regular practice.
- Find Weak Areas and focus revision accordingly.
Best Books for IISER 2026 Preparation
Selecting the right study resources can streamline preparation and improve conceptual clarity.
| Book Name | Subject | Best For | Level |
|---|---|---|---|
| NCERT Class 11 & 12 | All Subjects | Foundation Building | Easy-Moderate |
| Concepts of Physics by H.C. Verma | Physics | Conceptual Understanding | Moderate |
| D.C. Pandey Series | Physics | Advanced Practice | Moderate-Hard |
| O.P. Tandon | Chemistry | Theory + MCQs | Moderate |
| Morrison & Boyd | Organic Chemistry | Concept Building | Advanced |
| Objective Mathematics by R.D. Sharma | Mathematics | Practice | Moderate |
| Problems Plus in IIT Mathematics | Mathematics | Advanced Problems | Hard |
| Trueman's Biology | Biology | Detailed Concepts | Moderate |
| MTG NCERT at Your Fingertips | PCB Subjects | Revision & MCQs | Moderate |
| Previous Year IISER Papers | All Subjects | Real Exam Practice | Exam Level |
Preparation Tips by Topper
Jeswin Kuriakose from Wayanad, Kerala, secured AIR 1 in the IISER Aptitude Test (IAT) 2025. His success highlights the importance of strong conceptual understanding, consistent practice, and disciplined preparation.
- Master NCERT Fundamentals: Build a strong foundation in Physics, Chemistry, Mathematics, and Biology from NCERT textbooks.
- Focus on Conceptual Learning: Prioritise understanding concepts rather than memorising formulas and facts.
- Solve Previous Year Papers: Practice IISER previous year question papers to understand the exam pattern and question trends.
- Take Regular Mock Tests: Attempt full-length mock tests to improve speed, accuracy, and time management.
- Strengthen Weak Areas: Analyse mistakes after every test and dedicate extra time to weaker topics.
- Revise Consistently: Maintain concise notes for formulas, reactions, and important concepts for quick revision.
- Balance All Subjects: Since IAT includes all four subjects, avoid neglecting any section.
- Develop Analytical Thinking: Practice application-based and multi-concept questions that are commonly asked in IISER exams.
IISER 2025 Expected Cutoff
Based on previous trends, student feedback, and overall difficulty level, the expected IISER 2025 cutoff is likely to remain competitive.
| Category | Expected Cutoff Marks |
|---|---|
| General | 115 – 130 |
| EWS | 105 – 120 |
| OBC-NCL | 95 – 115 |
| SC | 70 – 90 |
| ST | 55 – 75 |
| PwD | 45 – 65 |
Actual cutoffs may vary depending on seat availability, number of applicants, and overall performance.
Candidates securing scores above the expected cutoff should participate actively in counseling and seat allocation rounds.
IISER 2025 Result
IISER 2025 Result was released through the official admission portal. Candidates could access their scorecards using their application credentials.
The result includes:
- Candidate Score
- Category Rank
- Overall Rank
- Qualification Status
- Counseling Eligibility
After the result declaration, qualified candidates proceed to counseling, document verification, and seat allotment rounds.
| IISER Previous Year Question Paper | |
|---|---|
| IISER Question Paper 2024 | IISER Question Paper 2023 |
| IISER Question Paper 2022 | IISER Question Paper 2021 |
| IISER Question Paper 2020 | IISER Question Paper 2019 |
| IISER Question Paper 2018 | IISER Question Paper 2017 |
| IISER Question Paper 2016 | |
IISER 2025 FAQs
Ques: How can I participate in IISER counselling process?
Ans: Candidates who qualify in IAT must register for counselling through IISER admission portal, fill in their institute preferences, and complete the required admission formalities within the stipulated timeline.
Ques: How are seats allotted during IISER counselling?
Ans: Seat allotment is based on the candidate's rank in IAT, category, seat availability, and the institute preferences submitted during counselling.
Ques: What documents are required during IISER admission process?
Ans: Candidates generally need to submit their Class 10 and 12 mark sheets, category certificate (if applicable), IAT scorecard, passport-size photographs, and other documents specified by the admission authority.
Download the PREPP App and attempt FREE IISER Mock Tests and get complete study material!
Comments