Hi,

To be eligible for admission to NIT a  candidate need to score 75% of marks in class 12 if he is a general category student and 65% of marks if he is a sc/st category student

Or

A candidate should be in top 20 percentile of his/her boards.

So if you are a general category student and not among the top 20 percentile of your board you will not be eligible for admission to nits.

Hope this helps.