Yes there is. There are certain ways and aspects on which percentile can be calculated for usage in JOSAA ranks. This way there are several percentile cutoffs (top 10 or top 20) which are predicted for the different state boards of education. You can check out the link as follows as it contains everything in detail related to your query

https://engineering.careers360.com/articles/top-20-percentile-cutoff-of-class-12-boards-for-iit-admission