When you apply to colleges and universities, many want you to report your overall high school grade point average. You can calculate your GPA based on the letter grades you received. Most GPAs use a four-point scale, but some school weight their GPAs by giving bonus points for more difficult classes. To find your GPA, you need to know your grades, how many credits you earned for each grade and how your school weights your grades.
Convert each letter grade to a 4 for an A, a 3 for a B, a 2 for a C, a 1 for a D and a 0 for an F.
If your high school awards an extra half-point for honors class and an extra point for advanced placement classes, for example, your B in an honors class becomes a 3.5 instead of 3 and an A in an AP class becomes a 5 instead of a 4.
Multiply the grade points for the letter grade by the number of credits earned for the class. If you get 3.5 points for an honors B and the class gives you two credits, multiply 3.5 by 2 to get 7 grade points.
Total the grade points earned in all of your classes.
Divide the total number of grade points earned by the total number of credits. If you earned 189 grade points and 50 credits, divide 189 by 50, for a GPA of 3.78.