How is the Cumulative GPA computed : At the end of semester or when you are graduating, your cumulative GPA is computed with formula. Cumulative GPA = (Total Grade points obtained ) / (total Credit hours taken ) Total Grade points you obtained = Grade in the class X Credit hours of the class. E.g. Lets say, you have taken a two 3 credit classes and you got B+ ( GPA 3.33) and C+ ( GPA 2.33) in them, cumulative GPA for these two classes is as below.