What is the approximate percentile needed in CAT to get a call from IIT's ?

See there is no fixed percentile for any college but still generally seeing the last year trends to get a call from IIT Bombay you need to get above 98+ percentile in order to get a call for interview and WSAT round.

For other IITs like IIT Delhi, Madras, Kanpur, Kharagpur you can get a call if you score above 90+ percentile.

Remember one thing along with this percentile you need to be an engineer and score above 50+ percentage in 10th 12th and graduation to be eligible for further evaluation in IITs. And you must be knowing that percentile is not the only thing after CAT ecan every IIT in which you have applied makes a merit list on the basis of aggregate score of individuals which consists of different parameters like CAT marks, 10th 12th and graduation percentage, work experience, extra curriculars which has different weightages for different colleges.

So you need to have a decent profile along with the percentile I mentioned above in order to get a call for interview and WSAT round. Also always aim for high percentile to increase probability of conversion.

All the best for your preparations and exams!!

It is relative . Some IIT have profile based call also while some have individual cut off which is based on applications also.