Hey Gaurav!

Here you go:

1) IIIT Hyderabad is the best among all the IIIT's and can be compared to IIT's. It was the first IIIT established. 

2) IIIT Allahabad comes next. It was established after IIIT Hyderabad. It offers B.Tech in IT. It can be regarded as one of the best institutes to offer an undergraduate course in B.Tech IT. If you don't get Hyderabad, Allahabad could be the option for you. Placement is great.

3) IIIT Bangalore is a fast frowing successful institute, hence ranked next.

Good Luck.