Vinod for getting admission into any of the IIT, only thing matters is your performance in JEE Advanced examination. 12th board percentage is not at all used for evaluation. The only thing which was required in the starting before JEE mains exam was that you need to have more than 75% in 12th board. You had a much more percentage in 12th so you were eligible to give JEE Mains exam which you cleared and have given JEE Advanced examination.

Now if you want to know what are your chances of getting admission in any of the IITs then you will need to tell me how much marks you can get in JEE Advanced examination which you must have already calculated with the help of unofficial answer keys available. With your marks only I will be able to tell your estimated OBC category rank and the chance of getting a seat into any of the IIT.

Feel free to ask if you have any more queries. All the best!!