Hello Ratnadip,

73 is a too low score to get admission in any of the IISERs. You need to score more than 120 out of 180 to get into the top IISERs like IISER Kolkata,IISER Pune, whereas scoring above 90 will keep you in safe side with the remaining IISERs with a lower branch. Since IISERs accept KVPY,JEE Advanced,JEE Main,SCB scores as well,one needs to perform well in IAT for admission into IISER.

Hope this Helps.

Stay connected for further queries.

All the Best!!