Hello aspirant

To be eligible for any NIT or IIT college you must score minimum 75% in PCM in board exam and 65% for reserved category . You must qualify for jee main for NIT and Jee advanced for IIT college. This comes under Eligibility criteria.

Now qualifying percentile for JEE main and jee advanced changes every year. That too is defferent for different categories. It depends on number of candidates appeared and qualified in exam, difficulty level of exam, previous year's cut off of that college etc.

2019 cut off of JEE main category wise is as follows

Common rank list               89.7548849

Gen EWS                               78.2174869

OBC  NCL                               74.3166557

sc                                             54.0128155

st                                             44.3345172

pwd                                           0.11371730

So to get admission to any nit or IIT college, you should score more than a above mentioned percentile

For more information you can refer to following link

https://engineering.careers360.com/jee-main-college-predictor

Candidate should satisfy one of the two criteria to be eligible for Jee Advanced-
The minimum requirement for general & OBC is at least 75% marks in aggregate and 65% for SC, ST & PwD in 12 or equivalent.
Candidates should be within category wise top 20 percentile of successful candidates in their respective 12 or equivalent.
http://engineering.careers360.com/articles/jee-advanced-eligibility-criteria

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