Hello Aspirant,
As we know that IITs are ranked among top engineering institutions in India and even IIT Roorkee, IIT Delhi, IIT Bombay and likewise are top IITs and there is very tough competition to get seat in it therefore the cut-off also goes very high for these institutions because seats are limited and aspirants are much numerous as compared to that of seats.
Now if you want to secure seat in the mentioned IITs with OBC category then you should have you CRL under 7,000 approx.
You can get details about previous year's cut-off for IITs from the link given below :-
https://engineering.careers360.com/articles/jee-advanced-cutoff-for-iits
I hope this information helps you.
Good Luck!!
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