i have got 42000 rank mains 2019.which nit can i get.

Your rank is not that good but it's quite enough to get you into some of the NIT's, if not into all of them. Since, you have not stated your category I believe you are from general category and considering the healthy competition it's difficult for you to get into top NITs. Below is the cutoff from last year of the NITs along with the branches of the general category:-

COMPUTER SCIENCE

• NIT, Arunachal Pradesh- 78000
• NIT, Manipur - 130000
• NIT, Meghalaya - 56000
• NIT, Mizoram - 218000
• NIT, Sikkim - 160000

CIVIL ENGINEERING

• NIT, Arunachal Pradesh - 230000
• NIT, Manipur - 150000
• NIT, Meghalaya - 225000
• NIT, Mizoram - 1050000
• NIT, Sikkim - 980000
• NIT, Jalandhar - 50000
• NIT, Agartala - 265000
• NIT, Durgapur - 43000

ELECTRICAL & ELECTRONICS ENGINEERING

• NIT, Meghalaya - 185000
• NIT, Mizoram - 800000
• NIT, Sikkim - 850000
• NIT, Goa - 60000

ELECTRONICS & COMMUNICATION ENGINEERING

• NIT, Arunachal Pradesh - 110000
• NIT, Manipur - 890000
• NIT, Meghalaya - 165000
• NIT, Mizoram - 800000
• NIT, Sikkim - 160000
• NIT, Goa - 56000

ELECTRICAL ENGINEERING

• NIT, Arunachal Pradesh - 165000
• NIT, Manipur - 350000
• NIT, Agartala - 180000
• NIT, Raipur - 49000

MECHANICAL ENGINEERING

• NIT, Arunachal Pradesh - 225000
• NIT, Patna - 45000
• NIT, Raipur - 90000
• NIT, Manipur - 750000
• NIT, Meghalaya - 275000
• NIT, Agartala - 260000
• NIT, Goa - 310000
• NIT, Jalandhar - 40000
• NIT, Durgapur - 45000

These are only the closing ranks of general category for their respective home states. I hope this answer clears your query.

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Dear Reader,

I cannot help you properly until i know your caste/category so just visit the link mentioned below and fill up all the details required and predict the colleges you are eligible for. For any more queries feel free to contact.

https://engineering.careers360.com/jee-main-college-predictor