How GPA Is Calculated
GPA looks like a simple average, but it isn't — and the part people miss is credit hours. Understanding how it's really computed tells you exactly which classes move your number and by how much.
Step 1: letters become points
Each letter grade maps to a number on the 4.0 scale. The common mapping:
- A / 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, D− = 0.7, F = 0.0
Step 2: weight by credit hours
This is the crucial part. Multiply each course's grade points by its credit hours to get quality points. A 4-credit course counts twice as much as a 2-credit one. So an A in a big lecture pulls your GPA up much harder than an A in a one-credit seminar.
Step 3: divide
Add up all the quality points and divide by the total credit hours. Example with three courses:
- A (4.0) × 3 credits = 12.0
- B+ (3.3) × 4 credits = 13.2
- A− (3.7) × 3 credits = 11.1
- Total quality points = 36.3, total credits = 10
- GPA = 36.3 ÷ 10 = 3.63
Weighted vs unweighted
The scale above is unweighted — an A is 4.0 in any class. Many high schools use a weighted scale that gives honors and AP courses a bonus (an A might be worth 5.0), which is why some students report GPAs above 4.0. Colleges typically recalculate to their own scale, so know which one a given number refers to.
Cumulative vs semester GPA
Your semester GPA covers one term; your cumulative GPAcovers all terms combined, weighted by credits. A great semester moves your cumulative GPA less as you accumulate more credits — early grades set a foundation that's harder to shift later.
How to raise your GPA
- Prioritise your high-credit courses — they carry the most weight.
- Retake a failed class if your school replaces the grade in the GPA.
- Front-load effort: early credits anchor your cumulative number.
Calculate yours
Add your courses, grades and credit hours to the GPA calculator to see your weighted GPA update instantly. For the underlying arithmetic, the percentage calculator may help too.