As of now its tough to say because the analysis and also cutoffs change every year due to many factors like total students appearing for exam,difficulty level of paper etc.as you did not mention your category considering you from general category now based  last year round 6 closing ranks,you need

Dear aspirant,

Hope you are doing well. As per your query yes Digi locker certificates are valid for any purpose infact it is legally valid as it is provided and written by CBSE at the end of every document. But you should always carry your actual documents for these type

Dear Student

I have to say BRAVO! Your rank is really good. However every IIT has a slightly different cutoff , so for your convenience I am giving you a link for JEE advanced cutoffs. You the link below to check whether you are eligible or not.

https://engineering.careers360.com/articles/jee-advanced-cutoff

As according to your marks by subject wise they are very less chances of Getting NIT's and IIT's.

As you can get through the below link:

https://engineering.careers360.com/jee-main-college-predictor?utm_source=qna&utm_medium=jee_cp