For JEE Main candidates can write the exam for a total number of 6 times over a period of three consecutive years. Each candidate will get two attempts in a year. Therefore, if a candidate has passed class 12th board exam in 2018 can give JEE main 2020 only, next year (2021) candidate can not appear for JEE Main. If the candidate has passed 12th exam in 2019 then the candidate can appear in 2020 and 2021 JEE Main. If the candidate is appearing for the class 12th board exam in 2020, then he/she can appear in both the sessions of JEE Main in years 2020, 2021 and 2022.