How to Calculate GPA: Step-by-Step (with Examples)

Calculating a GPA comes down to two numbers per course: the letter grade and its credit hours. Multiply the grade’s point value by the credits, add everything up, divide by total credits — that’s the whole formula. This guide walks through it step by step, with a worked example and the mistakes that trip most people up.

The formula

GPA = Σ (grade points × credit hours) ÷ Σ credit hours

First, convert each letter grade to grade points using your university's scale. The most common scale in the US and many international programs is the 4.0 scale: A = 4.0, A− = 3.7, B+ = 3.3, B = 3.0, B− = 2.7, C+ = 2.3, C = 2.0, C− = 1.7, D+ = 1.3, D = 1.0, F = 0. Some institutions award A+ and use a 4.3 scale — always check which one your transcript uses.

Worked example

Suppose this term you took three courses:

• Calculus I: 4 credits, grade A → 4.0 × 4 = 16.0 points
• Physics I: 3 credits, grade B+ → 3.3 × 3 = 9.9 points
• English Composition: 2 credits, grade A− → 3.7 × 2 = 7.4 points

Total grade points = 16.0 + 9.9 + 7.4 = 33.3. Total credits = 4 + 3 + 2 = 9. Divide: 33.3 ÷ 9 = 3.70. Your semester GPA is 3.70.

Three mistakes that ruin GPA calculations

• Averaging grades without credit weighting. A 1-credit elective must not move your GPA as much as a 4-credit core course.
• Using the wrong scale. On a 4.3 scale, an A+ is worth 4.3 — mixing scales changes every course.
• Forgetting plus/minus grades. An A− (3.7) is not an A (4.0).

What about CGPA?

GPA usually means one term; CGPA (cumulative GPA) covers everything you've completed. The math is the same, but the denominator includes every credit you've ever earned. You can calculate yours by combining your previous CGPA and credits with this term's courses.

Skip the manual math: use the free GPA Calculator or the CGPA Calculator — both show their formulas and update live as you type.