A candidate can attempt JEE Main for three consecutive years starting from the year they pass Class 12. Since the exam is conducted twice every year (typically in January and April), a candidate can appear in up to six sessions in total across three years. If a student appears in both sessions in the same year, the better score is considered for ranking purposes. Candidates are not required to appear in both sessions, and appearing in one session does not restrict them from appearing in the other.