IISER 2025 Question Paper Analysis: IAT 2025 Answer Key (May 25), Diificulty Level & Expected Cut Off
Indian Institutes of Science Education and Research Entrance Exam 2026 ( IISER Entrance Exam )
IISER 2025 Question Paper and Answer Key PDF will be released on May 25, 2025, after the examination is successfully conducted. The exam will be held to test the candidate's domain knowledge in Physics, Mathematics, Biology and Chemistry. Read this Shiksha article to know IAT 2025 Question Paper Analysis and answer key details here.
IISER 2025 Exam Question Paper and Answer Key
IISER 2025 Exam was conducted successfully on May 25, 2025, from 9 am to 12 pm at various exam centres across the nation. Exam officials will test candidates domain knowledge in Chemistry, Biology, Physics and Mathematics in the form of MCQ questions for the duration of three hours.
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The overall IAT 2025 exam difficulty level was moderate. Candidates who had opted for PCM found the Biology section tough to attempt, and candidates who had PCB in their class 12 found the Mathematics subject questions difficult to solve. Topics were equally distributed from the IAT 2025 syllabus. Preparation from NCERT Books will help the candidates to have a good IAT 2025 score.
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The IISER Entrance Exam questions are objective type. These are multiple-choice questions with four options. The mode of the exam is computer-based. Test-takers have to select one option. Marks per question is four. One mark will be removed for wrong answers.
Indian Institutes of Science Education and Research (IISER), the examination conducting body already released the IISER Aptitude Test (IAT) 2025 Student Response Sheet on second week of June 2025. Candidates can visit the official website of IISER and after logging in with their credentials can finally view their IAT 2025 Response Sheet. Candidates can finally tally up their marks scored in the IISER Aptitude Test which conducted in the first week of June 2025.
The IAT 2025 question paper here in this article is designed after the IISER 2025 analysis and students' reactions. IISER 2025 questions have become very dynamic, and questions are more based on a practical and analytical approach than one-word answers. In the coming years, the questions will come from the disciplines, that are flourishing in the science domains, and there is no such need to mug up the concepts.
- ISER 2025 Question Paper and Answer Key
- IISER 2025 Exam Analysis
- IISER 2025 Exam Difficulty Level
- IISER Entrance Exam 2025: Chapter Wise Weightage
- IISER 2025 Expected Cut Off
ISER 2025 Question Paper and Answer Key
The exam officials will be releasing the IAT 2025 answer key on the official website. Candidates can check the 2025 question paper and answer key from the below-mentioned link.
| IISER 2025 Question Paper & Answer Key |
Available Soon |
IISER 2025 Exam Analysis
Based on the student reactions, IISER 2025 overall exam difficulty level was moderate. Candidates who are from PCB stream found Biology very easy and took more time for Mathematics questions. Equal distribution of subjects and topics was found in the exam. Both the practical and theory-based questions were asked by the exam officials. Many of the students found the physics section as the most difficult section to attend. Questions in physics were mostly application-based based and the electricity topic had the highest weightage of questions.
Questions in biology were technical and practical-based; no repeated questions were asked in this section.
IISER 2025 Exam Difficulty Level
Candidates can check out the IISER 2025 exam difficulty level from here:
| Subject |
Difficulty Level |
Good Attempt |
|---|---|---|
| Biology |
Easy |
12-13 Questions |
| Physics |
Moderate to Difficult |
8-10 Questions |
| Chemistry |
Moderate |
10-12 Questions |
| Mathematics |
Easy to Moderate |
10-12 Questions |
Check out the overall exam difficulty level of IAT 2025 based on Student Reactions:
| Difficulty Level | Percentage |
|---|---|
| Easy | 18% |
| Moderate | 64% |
| Tough | 18% |
IISER Entrance Exam 2025: Chapter Wise Weightage
Check out the IISER exam 2025 chapter wise weighatge of Mathematics, Physics, Chemistry and Biology subjects from here:
Physics Chapter-wise Weightage
| Chapter |
Approx. No. of Questions |
|---|---|
| Kinematics |
1–2 |
| Laws of Motion |
1–2 |
| Work, Energy & Power |
1 |
| Rotational Motion |
1 |
| Thermodynamics |
1–2 |
| Oscillations & Waves |
1 |
| Electrostatics |
1 |
| Current Electricity |
1–2 |
| Magnetism & EMI |
2 |
| Optics |
1–2 |
| Modern Physics (Atoms/Nuclei) |
1–2 |
Chemistry Chapter-wise Weightage
| Chapter |
Approx. No. of Questions |
|---|---|
| Atomic Structure |
1 |
| Chemical Bonding |
1–2 |
| Thermodynamics |
1 |
| Equilibrium |
1–2 |
| Redox Reactions & Electrochem. |
1 |
| Chemical Kinetics |
1 |
| Organic Chemistry – Basics |
1–2 |
| Hydrocarbons & Functional Grps |
2–3 |
| Coordination Compounds |
1 |
| Biomolecules |
1 |
Mathematics Chapter-wise Weightage
| Chapter |
Approx. No. of Questions |
|---|---|
| Sets, Relations & Functions |
1 |
| Trigonometry |
1 |
| Algebra (Complex, Quadratics) |
2 |
| Calculus (Limits, Derivatives) |
2–3 |
| Integrals & Applications |
1–2 |
| Vectors & 3D Geometry |
2 |
| Probability |
1–2 |
| Matrices & Determinants |
1 |
Biology Chapter-wise Weightage
| Chapter |
Approx. No. of Questions |
|---|---|
| Cell Structure & Function |
1–2 |
| Genetics & Evolution |
2–3 |
| Human Physiology |
3–4 |
| Plant Physiology |
2 |
| Reproduction |
1 |
| Biotechnology |
1 |
| Ecology |
2 |
| Diversity of Life/Structural Org. |
1 |
IISER 2025 Expected Cut Off
IAT 2025 candidates' ranks will be based on their combined scores from the four sections (Physics, Chemistry, Mathematics and Biology). The exam comprises 60 questions with a total score of 240 marks. Below is a table for the expected IISER 2025 ranks corresponding to different score ranges.
| IISER 2025 Score (Out of 240) |
Expected IISER 2025 Rank |
|---|---|
| 200 and above |
Rank 1 to 80 |
| 200-160 |
Rank 81- 200 |
| 160- 110 |
Rank 201 to 800 |
| 110-95 |
Rank 800 to 1500 |
| 95-75 |
Rank 1500- 2000 |
| < 60 |
Above 2000 |
Also Read: IISER 2024 Marks vs Rank: Check Cut off and Opening- Closing Ranks
IISER 2024 Question Paper and Answer Key
The exam officials have released the IAT 2024 answer key on the official website. Candidates can also check the 2024 question paper and answer key from the below-mentioned link. Candidates must note that option A of the released questions paper is the correct answer in the PDF.
Download IAT 2024 Question Paper and Answer Key Here:Download Now
Read More: IISER Question Paper Analysis (OUT): IAT 2024 Answer Key Released
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Student Forum
Anything you would want to ask experts?Answered Yesterday
The IISER exam is conducted in a single shift. The exam time is from 9 AM to 12 PM. Students can check the IISER admit card to know exam dates.
V
Contributor-Level 8
Answered 2 weeks ago
No, the IISER Entrance Exam result can be checked only in online mode. The exam authorities will release the result or rankcard on the exam website. Students have to login with their registration credentials to download the IISER Aptitude Test result.
V
Beginner-Level 5
Answered 2 weeks ago
IISER Entrance Exam centres are located in cities across India. The exam is not conducted outside India. In case there is a change this year, it will be updated here.
L
Beginner-Level 5
Answered 2 weeks ago
No, there is no option to apply for the IISER Entrance Exam in offline mode. Students have to go to the exam website, which is iiseradmission.in to apply for the exam. The fee has to be also paid in online mode, through Credit/Debit Card or Net Banking.
P
Beginner-Level 5
Answered 2 weeks ago
If you are planning to appear for the IISER Entrance Exam 2026, and you will write your Board exam in the same year, you will be eligible. In case you are slated to appear for the exam in 2027, you cannot take the IISER Entrance Exam 2026. The exam is expected to be conducted in May. If you do not c
N
Beginner-Level 5
Answered 2 weeks ago
No, IISER Entrance Exam is conducted in a single day and slot. The total duration of the exam is three hours. There is no break in between the test. IISER Aptitude Test is conducted in computer based mode.
M
Beginner-Level 5
Answered 2 weeks ago
The IISER Entrance Exam Mock Test can be taken from the exam website for free. There is no fee involved for this. Neither is it necessary to register for the IISER Aptitude Test. Students can take the mock test as many times as they wish to.
A
Beginner-Level 5
Answered 2 weeks ago
Yes, it is mandatory to attempt all questions of the IISER Entrance Exam Mock Test at one go. The mock test gets disabled within a few minutes of inactivity. Hence, students should solve all questions within 180 minutes of starting the test. If you are unable to complete the IAT mock test in one sit
Contributor-Level 10
Answered 2 weeks ago
Yes, the questions of the official IISER Entrance Exam Mock Test are from the syllabus. The total duration of the mock test is 3 hours. It will provide familiarity with the IISER Aptitude Test and help in preparation.
A
Beginner-Level 5
Answered 3 weeks ago
The IISER entrance exam is of 240 marks. Each question carries four marks. There is a minus one mark for each wrong answer. No marks will be removed for questions not answered. There are 60 marks in each of the four sections. All questions are objective type and have four answer options. Students ha
M
Beginner-Level 5
IISER Entrance Exam Notifications
The IISER Entrance Exam 2026 pattern is expected to remains same as last year. IAT consists of 60 questions, 15 questions each from Biology, Chemistry Mathematics, and Physics. There will be four answer options. Total time for answering the test is 180 minutes. Questions are multiple choice type with only one correct answer. The mode of the exam is computer-based.