Hello Aspirant,

See JEE-Main pattern has been changed in 2019 when the conducting authority was transferred from CBSE to National Testing Agency (NTA). Now JEE-Main is conducted twice in a year, first attempt in January and second in April month. In each attempt various shifts are allotted to the respective candidates to avoid over crowding and smooth conduction of an examination. There are two shifts in a day in which JEE-Main is conducted in both the attempts. First shift starts from 9:30 AM and gets over on 12:30 PM whereas second shift starts from 2:30 PM and gets over at 5:30 PM. You have to only appear for any one shift as allotted by NTA in your admit card.

For complete details about JEE-Main kindly check out the link given below :-

https://engineering.careers360.com/exams/jee-main

I hope this information helps you.

Good Luck!!