What would be my JEE mains rank?

Your percentage is excellent but ur JEE marks are not enough to get into IIT's. But u may get NIT's, Delhi College of Engineering, COEP, Lovely Professional University.

I can't predict your rank exactly, but i can tell you that you won't get any NIT with these marks.

You can use online rank predictor, they predict rank which is most accurate. Use the rank predictor of good coaching institute, as they have enough data to make accurate calculation and they predict with good accuracy.