Hello aspirant

Congratulations for getting 123 marks in jee main it is really good marks.jee main cutoff vary every year based on different factors that's why we can predict this year cutoff by analysing past year cutoffs.as you have not mentioned your category it will be difficult to predict percentile with accuracy as category percentile is different.

Factor affecting cutoff-

1. No of seats

2. No of students

3. Difficulty of papers.

4.Last year cutoff

Your Overall Percentile is: 97.7 - 97.9

Your Predicted Rank is: 19183 - 21333

You can get best college according to your rank by using this predictor

https://engineering.careers360.com/jee-main-college-predictor?icn=QnA&ici=qna_answer

Hope this will help you

Best of luck