See the admissions are completely dependent on the cut-off that changes every year.Calculate your rank in the JEE Main rank predictor(though this isn't final as NTA decides the final percentile only after April,2018):

Link:-https://engineering.careers360.com/jee-main-rank-predictor?icn=JEE_Main_rp&ici=clevertap

if your rank is within 50000,you are likely to get into NIT or any other good college but your choice of branch is not guaranteed.