GPA: quality points divided by credit hours
A GPA is a weighted average, and the weights are credit hours. On the standard 4.0 scale each letter grade carries quality points per credit: A = 4.0, B = 3.0, C = 2.0, D = 1.0, F = 0 (plus/minus variants typically shift by 0.3, e.g. A− = 3.7, B+ = 3.3 — the exact table is your institution's to define).
The formula is one line: GPA = total quality points ÷ total credit hours attempted. Concrete example — a semester with 12 credits at 3.5 and 15 credits at 3.2:
- Quality points: 12 × 3.5 = 42; 15 × 3.2 = 48.
- Total points: 42 + 48 = 90. Total credits: 12 + 15 = 27.
- Cumulative GPA: 90 ÷ 27 = 3.33.
Notice the leverage structure: a 4-credit course moves the needle four times as much as a 1-credit course at the same grade, and early semesters matter more because they carry a larger share of the running average. As terms accumulate, each new term has less power to change the cumulative number — a 3.30 after four semesters needs a genuinely exceptional term to move by a tenth of a point.
Weighted GPA adds a point for honors, AP, or IB coursework (so an A in AP Biology might count as 5.0 instead of 4.0), which is why weighted GPAs can exceed 4.0 and are not comparable across schools with different conventions. Unweighted GPA caps at 4.0 and measures the grade regardless of course rigor. Admissions readers commonly evaluate both — weighted for rigor, unweighted for raw performance — alongside class rank, which is simply your GPA's percentile position among graduating peers.