Some of the top branches in IIT's you can consider studying are:

• Computer Science Engineering
• Mechanical Engineering
• Electrical Engineering
• Chemical Engineering
• Aerospace Engineering

The prospects of branches mentioned above are good and high in today's time. There can be top branches in each IIT as well, as per their specialization in a particular branch.

Like in IIT Bombay, Computer Science is on top. In IIT Delhi its Electrical Engineering and Mechanical engineering etc.

So in case you want to know for any specific IIT then you can mention the name.

Good Luck.