Hello Mahesh

Assuming you to be a general caste student, for Mumbai IIT, your rank should be under 1000 in JEE advanced. Cut off also depends on the branch you are opting for. I am providing you with a link for all the details regarding cut-off for Mumbai IIT.

https://engineering.careers360.com/articles/jee-advanced-cutoff-for-iit-bombay

This article will help you with all your queries.

Hope you feel this information helpful.

Thanks!!