The marks and percentage varies greatly as they depend on many factors some like number of candidates appearing and also the paper level, etc. So you can rely somewhat on rank basis. It also depends on your stream as well right. For example streams like Textile Technology Enginerring has cutoff closing rank around 5431 in IIT DELHI where as CS has cutoff closing rank 186.
to know the cutoffs of IIT DELHI of various branches in detail, refer to the following site..
https://engineering.careers360.com/articles/iit-delhi-cut-off
Check the nsit DELHI and DTU cutoff here.. https://engineering.careers360.com/tags/nsit-delhi-be-cutoff
https://www.careers360.com/university/delhi-technological-university-delhi
In short you need to score around 230 and above in JEE mains to get a very good rank to get into these renowned institutes.
Best wishes. Thank-you.
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