Hi Aditya --
Yes, the schools all know how different the Indian universities are in terms of how they grade and relative rank. Your target schools will understand how to interpret your grades. If you're nervous about it, then you can write the optional essay to explain - but it needs to be handled carefully (sometimes people are too assertive in their claims in such an essay and it can be a turnoff - you'd want to lay out the facts and leave it up to the adcom to do the actual interpretation). You might also include a note in your resume that gives the actual % of your class topper if you know it, which could use as comparison. Be sure to only report actual facts though, no guessing!
This is a topic that comes up a lot and all of the adcoms are aware of it, so you don't need to worry. You can always reach out to your schools directly though - this is a question that they receive frequently and they'll be able to assure you better than some snarky person on an Internet forum probably can.
Good luck, BTW - those are great schools!
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