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 )
Admit Card - 24 May '26 - 7 Jun '26
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.
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.
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 3 weeks ago
IISER answer key will be released on June 7, 2026. Candidates can download the answer key online. The answer key challenge window will open on June 9, 2026.
V
Contributor-Level 10
Answered 3 weeks ago
The IISER exam date is June 7, 2026. The exam will commence at 9 AM and continue till 12 PM. It is a computer-based test.
V
Contributor-Level 10
Answered 4 weeks ago
IISER score 200 or above is a good marks. It can help to get admission to IISER Pune and IISc Bangalore. Candidates must have a good conceptual knowledge, give priority to all four subjects. Prepare for the exam according to the exam syllabus and take mock test to score above 200.
V
Contributor-Level 10
Answered 4 weeks ago
Based on previous year analysis, IAT exam is moderately difficult. It requires strong conceptual knowledge. Students who have prepared properly for exam can easily score good marks.
V
Contributor-Level 10
Answered a month ago
It is quite difficult for the GEN / OBC category to get admission to IISER with 50 marks. Even the reserved category students have less chance in the later counelling round for admission. To secure admission, students must score above 150 marks.
V
Contributor-Level 10
Answered a month ago
IISER exam is considered of moderate difficulty level. Majority of students finds Physics, and Mathematics challenging. PCM students may find biology tough while PCB students might find Mathematics tough. However, the difficulty level of IISER compared to JEE Main and Advanced is moderate to easy.
V
Contributor-Level 10
Answered a month ago
The last date to apply for IISER 2026 was April 13, 2026. IAT application form was available on the website, iiseradmission.in.
V
Contributor-Level 10
Answered a month ago
IISER 2026 application is available from March 5 to April 13. Eligible candidates can fill the application form online at iiseradmission.in. The process to fill the application form is registration, form filling, and payment of fees.
V
Contributor-Level 10
Answered a month ago
IISER Berhampur released the application form for IISER 2026 on March 5, 2026. The registration link is updated on the website, iiseradmission.in.
V
Contributor-Level 10
Answered a month ago
IISER 2026 application fee is updated online. The application fee for IISER 2026 is Rs. 2000 (General, EWS, OBC, and OBC-NCL). For other categories, the fee is Rs. 1000.
V
Contributor-Level 10