IIT JAM

You need to clear the graduation with at least 55% aggregate marks in relevant subject areas are eligible to appear for IIT JAM exam. For further details, please refer to the link below:
https://www.shiksha.com/science/articles/colleges-accepting-iit-jam-scores-ranks-for-admission-blogId-13971.

IIT JAM, 2018 Subject-wise Cut off is mentioned below. Please check, if you made the cut from the marks mentioned below. In Physics, qualifying marks for general category are 19.51 while for SC/ ST/ PWD, it is 9.76. For Physics Paper/
In Chemistry, qualifying marks for General Category students are 14.79 and 7.39 for SC/ST/PWD. For Chemistry Paper of IIT JAM 2018. In Mathematics, qualifying marks for General Category are 23.35 and 11.68 for SC/ST/PWD. Based on IIT JAM Result 2018, candidates will be admitted to Institutes according to the preference of choices filled by them in Admission Form. Regards.

It is difficult to predict your rank based on the marks obtained in the exam. Request you to wait for ranks to be made available by the exam authorities. The IIT JAM 2018 exam was successfully conducted on 11th February 2018. Those who have appeared in the exam can now see their IIT JAM result on 20th March 2018.
Regards.

Although you have completed your UG degree, you need a minimum pass percentage of 55% in your UG degree to qualify for the JAM. Please refer to the link provided below for a detailed eligibility criteria for the JAM exam. Regards. https://www.shiksha.com/science/exams/iit-jam.

Yes, you are eligible. You need to have a Bachelor's degree in Physics or Mathematics or CSE or EE or ME. You need to appear for JAM exam for admission in this course.

The expected subject-wise Cut off of IIT JAM 2018 is mentioned below. Based on these cut offs, the total test population and marks obtained by candidate, rank of candidates are decided. IIT JAM Cut offs vary according to the categories.
IIT JAM Chemistry Cutoff:
General-27
OBC-22.40
SC/ST-13.5
Regards.