Your rank should be under 2500 to get IIT Bombay. Cut off varies according to branches as well.

Are you looking for any specific branch?

To check the cut off branches wise you can refer below link

IIT Bombay Cut off

All the Best!!

As the exam pattern of Jee Advanced keeps on changing year wise so it is quite difficult to provide any marks or rank range but it would be better to get more than 60% to get admission in IIT Bombay and other top IITs as well. For more information, you can go through the below provided cut off 2017 article as well -

Jee Advanced 2017

Good Luck!!!!