Candidates can check B.Tech Cut off for Top IITs & NITs here.
Hii aspirant..
If you are taking one year drop after you BTech before doing your Mtech than there is no issue. Rather than spending this one year I tell I would suggest you to have some job experience and get in touch with companies and recruiters.
The 1 year drop that you take will not affect your CV much and even the Drop is not going to be objection by IIT for MTech admission.
Hope it helps.
Best of luck
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