Hello student you can calculate and get your rank by using this formula

100 - (your total percentile) *869010 /100.

In your case your rank must be around 225, 942.

Cut off vary every year on various factors like the level of question in the entrance examination and total number of applicants in that examination with your rank its difficult to get admission in NIT's as we all know that seats are very limited and admission is directly based on merit rank.

To check cut off for NIT's you can refer to the link mentioned below - https://www.google.com/amp/s/engineering.careers360.com/articles/jee-main-cutoff-for-top-nits/amp

Feel free to comment if you have any doubt

Good luck