Hello Aspirant

What is the Percentile Score?

Percentile scores are based on the relative performance of all those candidates who appear for the examination. It obtained after transforming the scores into a scale ranging from 100 to 0 for each session of examinees.

Percentile Score shows the percentage of candidates who have scored equal to or below a particular percentile in an exam. It is the normalized score and not the raw scores. After normalization, each topper of a session will get the same percentile of 100 which is the desirable one. Also the marks between the lowest and highest scores are also converted to the respective percentiles. 

So how will the JEE Main 2019 scores for Paper 1 be calculated?

The formula to be used will be:

10 x no. of students with raw score less than or equal than the candidate/total no of students appeared in the sessio n

Note: To avoid bunching effect and reduce tie breaking, the Percentile Scores will be calculated up to 7 decimal places.

What will be the Highest Raw Score and Percentile Score?

Since the calculation is per session, all the highest raw scores will have normalized Percentile Score of 100 for their respective sessions.

for more details

https://engineering.careers360.com/articles/jee-main-normalisation-process-how-scores-are-calculated

Hope this helps you

Good Luck