Hello Aspirant,

Like any other exam, the cut-off for IISER test is also not a constant.
It changes every year, but the difficulty is usually about the JEE mains level, with a few advanced type questions.
Results are out within 2 days of the test, and if you are selected,
your name, the allotted IISER would be listed.

Still as far as an estimate is concerned :

For IISER Pune & Kolkata ( General Category ) : 110/180

For IISER Pune & Kolkata (SC Category) : 98/180

ANY other IISERs ( General Category ) : 70/180

ANY other IISER (SC category) : 57/180

You can read more about IISER Aptitude Test by clicking at this link - https://engineering.careers360.com/exams/iiser-aptitude-test

Hope this was helpful.