See each year this will vary as they specify the date of birth so this year general category students whose date of birth falls on or after October 01, 1993 are eligible. for SC/ST/PwD it is relaxable by 5 years so their Date of birth has to be on or after October 01, 1988. this has to be as per the class 10th certificate. Also you can attempt JEE Main three times but only if you have passed your class 12th in 2016, 2017 or are appearing in 2018. This is the basic eligibility which you must meet before the others.