Hello Vasavi,

You can calculate a percentile score using the formula I am mentioning below:

Percentile Score of a Candidate = 100 x (Number of candidates who secured a raw score (or actual score) EQUAL TO OR LESS than the candidate) / (Total number of candidates who appeared in that session)

On the other hand you can go for some onine predictor as well as some of them are free and some are paid.These predictor also help in prediction of rank as well.

Hope it helps.

Thank you :)