IISER IAT: Exam Pattern, Syllabus, Eligibility and Preparation

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The IISER Aptitude Test (IAT) is the national entrance test for undergraduate admission to the seven Indian Institutes of Science Education and Research: Berhampur, Bhopal, Kolkata, Mohali, Pune, Thiruvananthapuram and Tirupati. It is conducted jointly by the IISERs and leads mainly to the five-year BS-MS dual degree, along with a few four-year BS and BTech programs at particular campuses.

IISER IAT is a single 3-hour computer-based test with 60 multiple-choice questions, 15 each in Biology, Chemistry, Mathematics and Physics, for a total of 240 marks. Wrong answers cost one mark. Your IAT rank is used in IISER seat allocation. This guide explains who can apply, how the paper is built, what to study and how to prepare.

IISER IAT at a glance

Full name	IISER Aptitude Test (IAT)
Conducted by	Indian Institutes of Science Education and Research (IISERs), jointly
Exam level	National
Held	Once a year, in recent years in late May or June
Mode	Computer-based test
Duration	3 hours
Subjects	Biology, Chemistry, Mathematics, Physics
Total marks	240
Negative marking	Yes, -1 for each wrong answer
Languages	English and Hindi
Leads to	BS-MS dual degree at all seven IISERs, plus selected BS and BTech programs
Official website	www.iiseradmission.in

IISER IAT important dates

These dates update automatically from Kosuki’s exam calendar. “Announced” dates come from the official notice; “Expected” months are based on past years.

!Dates can change. Always confirm on the official website. Report a wrong date · How we check dates

What is IISER IAT?

IISERs are research-focused science institutes set up by the Ministry of Education. In recent cycles, the IISER Aptitude Test has been the main entry route to their undergraduate programs, replacing an earlier mix of channels. Students who want a science degree with early exposure to research take IAT alongside or instead of engineering and medical entrance tests.

Besides the BS-MS dual degree, recent cycles have offered programs such as BS in Economic Sciences and BTech programs at IISER Bhopal, BS in Economic and Statistical Sciences at IISER Tirupati, and specialized BS-MS tracks such as Computational and Data Sciences at IISER Kolkata. The list can change, so check the current brochure.

IISER IAT eligibility

Eligibility is based on your Class 12 year of passing, your subjects and your marks. The conditions below come from recent admission notices.

• Class 12 (or equivalent) passed in the science stream in the current year or the two previous years, as stated in each year’s brochure.
• At least three of these four subjects in Class 12: Biology, Chemistry, Mathematics and Physics.
• Minimum aggregate of 60% in Class 12 for General, EWS and OBC-NCL candidates, and 55% for SC, ST and PwD candidates, or the equivalent grade.
• Mathematics in Class 12 is required for some programs, such as the BTech and Economics programs; check the program list before choosing.
• There is no age limit in recent brochures.

IISER IAT exam pattern

IAT is a single paper with four equal sections. All questions are multiple choice with four options and one correct answer. You can move between sections freely within the 3 hours, which gives you three minutes per question on average.

The paper is offered in English and Hindi.

Section	Questions	Marks
Biology	15	60
Chemistry	15	60
Mathematics	15	60
Physics	15	60
Total	60	240

IISER IAT marking scheme

The marking scheme rewards accuracy. A wrong answer takes away a quarter of what a correct answer earns, so random guessing across four options gives no advantage on average. Guess only when you can eliminate at least one or two options.

• Correct answer: +4
• Wrong answer: -1
• Unanswered: 0
• All four sections count toward your total and rank.

IISER IAT syllabus

The IAT syllabus is based on the Class 11 and 12 science curriculum, broadly following NCERT books. Questions test concepts and reasoning more than rote recall. The IISER admission site publishes a subject-wise syllabus for each cycle.

• Physics: mechanics, thermodynamics, oscillations and waves, electrostatics, current electricity, magnetism, optics, and modern physics.
• Chemistry: physical chemistry (mole concept, equilibrium, kinetics, thermodynamics), organic reactions and mechanisms, and inorganic chemistry including periodic properties and coordination compounds.
• Mathematics: algebra, trigonometry, coordinate geometry, calculus, vectors and 3D geometry, probability and statistics.
• Biology: cell biology, genetics and evolution, human and plant physiology, ecology, and biotechnology basics.

IISER IAT result and seat allocation

After the exam, a provisional answer key is released for objections. The result gives your score and ranks, including category ranks. A rank alone does not guarantee a seat.

Seats are filled through an online allocation process on the IISER admission portal. You choose programs and campuses in order of preference, and seats are offered in rounds based on your rank, category and choices. You accept an offer by paying a seat-acceptance fee and then report to the institute with documents that confirm your eligibility, including your Class 12 marks.

How to prepare for IISER IAT

Every subject has the same weight, so a weak subject costs as much as a strong one earns. Students from a PCM background should spend real time on Biology, and PCB students on Mathematics, since only your total counts.

• Build your base on NCERT Class 11 and 12 for all four subjects; many IAT questions test NCERT concepts in a reasoning-heavy way.
• Use your weakest subject as your daily first task. Even 8 to 10 correct answers there changes your rank a lot.
• Practice the +4/-1 rule: in mocks, track how many guesses turned out right, and stop guessing blind if the ratio is poor.
• Solve past IAT papers from the official site and older KVPY SA and SX papers, which have a similar style.
• Take full 3-hour mocks and plan your section order; many students start with their strongest subject to bank marks early.
• Log your section-wise mock scores in Kosuki to see which subject is holding your total back.

How to apply for IISER IAT

1. Go to the official IISER admission website when registration opens and create an account.
2. Fill in personal and academic details, including your Class 12 board and subjects.
3. Choose your preferred exam cities.
4. Upload your photograph, signature and category certificates if applicable.
5. Pay the application fee online and submit the form.
6. Download the admit card from the portal before the exam.

IISER IAT FAQs

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Sources

• www.iiseradmission.in
• news.careers360.com/iiser-iat-2026-june-7-registration-march-5-april-13-bs-ms-btech-admissions-seven-iisers-pune-bhopal-mohali-kolkata-aptitude-test/amp
• www.collegepravesh.com/entrance-exams/iiser-aptitude-test

Last reviewed September 2026 against the official IISERs notice and information brochure. Exam rules can change from year to year, so always confirm details on the official website before you apply. Kosuki is independent and is not connected with any exam body. Spotted something out of date? Write to contact@kosuki.com.