Dear Shrawan Kher,
You can attempt IIT-JEE only once after your Class 12 .
You totally have two goes at IIT-JEE .....one in the year which you wrote your Class 12 Board Examinations & another the year after that !!
That's all ! This condition applies to Engineering Entrance Examinations like BITSAT,ISAT etc..,
The only exception is the AIEEE which you can attempt in 3 consecutive years for 3 times !
All the Best & Good Luck !!
Hope this helped you immensely..!!
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