Hello student ,

As you have not mentioned about which branch 's cut off you are asking for that's why it would be tough to tell you about the cut off of 2019 as it vary according to different course. So i will suggest you that visit the official website of iist to know the cut off of previous year . Further to be eligible for the exam you must have score 75% in 12th  board exam and 60% in JEE adv to get shortlisted in admission process . Only after that you qualify jee advance you are eligible for applying IIST exam for admissions.

Hope it helps !