Assign numbers to all of your letter grades. Give a D the value of 1. Give a C the value of 2. Give a B the value of 3. Give an A the value of 4. An F gets a zero and won't count toward your grade point average. Now add up all the numbers and get a grand total. Divide that grand total by how many grades you used (count up all the letters and that is the number you use to divide into the grand total). This is your grade point average. A perfect score of 4.0 means you got all As. Ignore any pluses and minuses on your letter grades.
Assign higher numbers to honors classes and advanced placement classes. Grades for honors classes receive a half point more than other grades for other classes. Grades for college-level or advanced placement classes receive a full point more. An A in an honors class receives a 4.5 value. An A in a college-level class receives a 5. Add up all the number values you assigned, and divide by the total number of letter grades. This is your weighted grade point average.
Calculate your GPA for several semesters. Calculate the grade point average for each semester by assigning 4 points to an A, 3 points to a B, 2 points to a C, 1 point to a D and zero for Fs. Add up these numbers and divide by the total number of grades you used. This is your average for that semester. Write the individual semester averages in a column going down your paper. In a second column next each semester average, put a .5 for each class that lasted only one semester. Example: .5 + .5 + .5 for three one-semester classes adds up to 1.5. Put a 1 for each class that lasted two semesters. Now multiply each semester average times the numbers in the second column. Add up all your totals and that is your weighted GPA.
Go online and find a grade point average calculator. Determine if you need a regular, weighted or cumulative grade point average, and go to that section. Carefully type in the numbers in the spaces provided, and the calculator will do the work for you.