Add up your grades, divide by how many classes you took — that's not your GPA, even though it feels like it should be. A straight average treats a one-credit seminar the same as a four-credit core course, and most schools don't grade that way.
Why credit hours change the math
A weighted GPA multiplies each course's grade points by its credit hours before adding anything up, then divides by the total credit hours — not the number of courses. An A (4.0) in a 4-credit class contributes four times as much as an A in a 1-credit class. Two students with identical letter grades can end up with different GPAs purely because of how many credits each course carried.
The actual formula
GPA = (sum of grade points × credit hours for each course) ÷ (sum of all credit hours). Grade points typically follow a 4.0 scale (A=4, B=3, C=2, D=1, F=0), though some schools use pluses and minuses (A- = 3.7, B+ = 3.3) which shifts the math slightly.
Working it out without the arithmetic
- Open the GPA Calculator and add a row for each course.
- Enter the letter grade (or grade points) and credit hours for each one.
- The weighted GPA updates instantly as you add or edit rows.
Cumulative GPA vs. semester GPA
A semester GPA only weighs that term's courses. A cumulative GPA carries every course from every term, which is why one rough semester rarely swings a multi-year cumulative GPA as much as it feels like it should — and why a strong semester takes a while to pull an earlier low GPA back up. For a single weighted grade calculated from assignment scores instead of full courses, the grade calculator handles that separately.