Hello

There is many factors that decide the cutoff of marks for iits or gfti , The factors are:

1 The difficulty level of the jee exam ,because if the exam were tough than cutoff may be lower than the previous years and vice versa.

2 Total candidates appears for the exam

3 Highest marks scored by the topper of that yearand many more ..

Usually about 85 percentile is required for iit or Gfti for general category and for reserved category it is around 70 percentile + .

Good Luck..