Engineering

Percentile indicates how many students have been outperformed by you in exam. Top 20 percentile means that you are ahead of 80% of the people. Your Rank = [(100 - percentile) x total number of students appeared in exam] /100
To calculate the JEE Main 2019 rank, you first need to know the percentage of people ahead of you with higher percentile scores. To calculate that, the formula would be 100 which is the highest score minus your percentile score. Since the percentile is calculated from a scale ranging from 100 to 0 for each session of examinees, the formula applies the total number of students in the January session which is 874469 /100 multiplied by the percentage of people who are ahead of you to arrive at the rank. Therefore, the formula to calculate the JEE Main 2019 rank for January 2019 is
JEE Main 2019 rank (probable) = (100- NTA percentile score) X 874469 /100
If NTA percentile score is 90.00, JEE Main rank will be (100-90.00) X 874469/100 = 97446
Consider the NTA score of 80.00 then JEE Main 2019 rank = (100-80.00) X 874469 /100. The rank will be 174893. * This formula would not be for a 100 percentile score as those are the top ranks.