Quick answer
The IISER Aptitude Test (IAT) is the only way into the seven IISERs (Berhampur, Bhopal, Kolkata, Mohali, Pune, Thiruvananthapuram and Tirupati) for their 5-year BS-MS and other undergraduate programmes: JEE ranks are not used. IAT 2026 had 60 questions (15 each in Biology, Chemistry, Mathematics and Physics) in 3 hours, +4 / −1, out of 240. You need 60% in Class 12 (55% for SC/ST/PwD) with at least three of Biology, Chemistry, Mathematics and Physics.
IAT 2026 at a glance
| Conducted for | BS-MS (Dual Degree) at all 7 IISERs, plus BS-MS Computational and Data Sciences (Kolkata), BS Economic Sciences and B.Tech programmes (Bhopal), BS Economic and Statistical Sciences (Tirupati) |
| Exam date (2026) | 7 June 2026; applications were open 5 March – 13 April 2026 |
| Pattern | 60 MCQs, 15 each in Biology, Chemistry, Mathematics and Physics; 180 minutes |
| Marking | +4 correct, −1 wrong, 0 unanswered; maximum 240 |
| Class 12 marks | 60% aggregate (55% for SC/ST/PwD), counting all subjects |
| Year of passing | Passed in the previous two years or appearing in the exam year (2024, 2025 or 2026 for IAT 2026) |
| Application fee (2026) | ₹2,000; ₹1,000 for SC/ST/PwD and some other categories |
| Seat acceptance fee (2026) | ₹35,000 (₹17,500 for SC/ST), adjusted against first-semester fees except the administrative part |
Subjects you need
- BS-MS (science): at least three of Biology, Chemistry, Mathematics and Physics in Class 12.
- Mathematics compulsory for BS-MS Computational and Data Sciences (Kolkata), the B.Tech and BS Economic Sciences programmes at Bhopal, and BS Economic and Statistical Sciences at Tirupati.
IISER or engineering?
Choose an IISER if you enjoy science for its own sake and want a research career: the BS-MS mixes classes with research projects from the early years, and many graduates go on to a PhD. Choose engineering if you want to build products and systems or want a job straight after four years. You can prepare for both: IAT covers the same Class 11–12 topics as JEE, plus Biology. Read our guide on how to become a scientist.
Science students in BS-MS programmes can also apply for the INSPIRE-SHE scholarship of the Department of Science and Technology. Similar 5-year integrated science programmes are offered at NISER Bhubaneswar and UM-DAE CEBS Mumbai through the separate NEST exam.
Can I get into IISER through JEE Advanced?
No. The official IAT 2026 brochure states that IAT is the only channel of admission to the IISERs.
What is the IAT exam pattern?
60 multiple-choice questions, 15 each in Biology, Chemistry, Mathematics and Physics, in 180 minutes. Each correct answer gets +4 and each wrong answer −1, for a maximum of 240.
How many IISERs are there?
Seven: Berhampur, Bhopal, Kolkata, Mohali, Pune, Thiruvananthapuram and Tirupati.
What marks do I need in Class 12 for IISER?
At least 60% aggregate, or 55% for SC, ST and PwD candidates, calculated across all subjects in the qualifying examination.