I got 99.41 percentile in jee mains 2020 January attempt, what could be my obc rank

Anish, Before any prediction of the ranks, kindly understand that the National Testing Agency (NTA) conducts two JEE papers viz. JEE MAINS PAPER1 and PAPER 2 for admission to B.Tech and B. arch courses respectively. You have not specified whether you want to inquire about your chances based on percentile secured in JEE MAIN PAPER-1 or JEE MAIN PAPER-2. So, I am going to answer your query taking into consideration that the query is about Paper2 and if your query was different, then you can let me know in the comments.

Now, to calculate your expected rank for B.Arch based on the percentile score that you have secured, you can use this formula:

So, (100 - your total percentile score) is the percentage of people ahead of you. Also, 112679 were the number of candidates who appeared for January exam.

Also,note that the ranks will change according to increase or decrease in the number of participants in the next session.

So rank formula is (100 - your total score) X 112679 /100.

Now, according to this formula, your expected rank is around 664. Note that it is the expected All India Rank and not your category rank which is very difficult to predict at this point of time but you can expect your category rank ie the OBC NCL rank to be under 350 according to the previous years trends but it may vary according to the difficulty level of the paper and the total number of candidates, so you cannot be certain about it, however, a prediction does help one in understanding his/her chances.

Also, if you want to predict your colleges based on these scores in the January JEE MAINS session, then you can use this rank predictor

https://engineering.careers360.com/jee-main-architecture-college-predictor?icn=JEE_Main_Paper_2_clgpd&ici=JEE_Main_Paper_2_article_view_sticky