Determine your letter grade using your class percentage.
Percentages can be converted to a letter grade:
A = 90 percent to 100 percent
B = 80 percent to 89 percent
C = 70 percent to 79 percent
D = 60 percent to 69 percent
F = 0 percent to 59 percent
Assign each letter a number using the GPA 4-point grading system.
Letter grades can be converted to a number in the 4-point system:
A = 4 points
B = 3 points
C = 2 points
D = 1 point
F = 0 points
Multiply each point by the number of units for each class. For example, if you got an A in a 3-unit class, you would assign 4 points to the grade and multiply it by 3, which equals 12. Do this for each of your classes.
Add each class total together to find your total grade points. Also add the total number of units you have attempted. Now divide your total unit points by the units attempted and you will have your GPA. For example, if you received three A grades and one B grade, all from 3-unit courses, you will have 45 total grade points. Since all classes are 3 units each, the total amount is 12 units. 45 total grade points divided by 12 units is a 3.75 GPA.