Grade Point Average, or GPA for short, is determined by each college courseâ€™s credit amount, semester hours and a personâ€™s individual class scores. They coincide with percentages and letter grades, but not all colleges and universities use the same scoring process. See the individual school for more information. The program below can help you convert your percent or letter grade into an accurate GPA. For example, a 1.8 GPA score is the numerical equivalent to a ‘C’ letter grade.