Hello dear student,

With this percentile you cannot expect to get admission into nits . This is not a very good score as at this percentile you can expect to get a rank in a range of 199,800- 199,900. While you can take admission in the colleges who accept the JEE mains marks .

If you want to calculate your rank by your own then dear student you can do it as total percentile score is the percentage  of people ahead of you. 869010 are the number of candidates appeared for Jan exam. So rank formula is (100 - your total score) X 869010 /100.

If the number of candidates for April exam increased to 1200000 then your final rank shall be (100 - your total score) X 1200000/100

I hope this is helpful for you dear student.

Best wishes