my percentile in mains 2020 is 89 and my category is general ews what might my rank be

Its difficult to predict the actual rank or JEE Advanced qualifying marks. But we can calculate your expected rank by this formula. Total 869010 candidates had appeared for the Jee Main January Session.
Then the rank formula is (100 - your percentile score) * (869010 /100) i.e. 95,591 which is your CRL rank.
If the number of candidates for April exam increased to 1200000 then your final rank shall be (100 - your percentile score) * (1200000/100).
For category wise ranking, you can use our rank predictor-
http://engineering.careers360.com/articles/jee-main-rank-predictor

Hello,

To predict the rank is very difficult it depends on various factors and even april attempt. To predict the rank please use the below formulae

100 - your 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