How Is GPA Calculated? The Formula Explained with Examples
GPA looks complicated until you realise it's just weighted averages. Here's exactly how it works — with real numbers, step by step, so you can do it yourself without a calculator.
The core formula
GPA is a weighted average — not a simple average. Each course contributes its grade point value multiplied by its credit hours. The formula is:
GPA = Σ(grade points × credit hours) ÷ Σ(credit hours)
Step-by-step example
Here's a typical semester. You took five courses:
| Course | Grade | Grade points | Credit hours | Grade points × Credits |
|---|---|---|---|---|
| Calculus I | A (4.0) | 4.0 | 4 | 4.0 × 4 = 16.0 |
| Intro Psychology | B+ (3.33) | 3.33 | 3 | 3.33 × 3 = 9.99 |
| English Comp | A− (3.67) | 3.67 | 3 | 3.67 × 3 = 11.01 |
| Chemistry Lab | C (2.0) | 2.0 | 1 | 2.0 × 1 = 2.0 |
| History Survey | B (3.0) | 3.0 | 3 | 3.0 × 3 = 9.0 |
| Totals | 14 | 48.0 |
Step 1: add up all the grade point products → 16.0 + 9.99 + 11.01 + 2.0 + 9.0 = 48.0
Step 2: add up all credit hours → 4 + 3 + 3 + 1 + 3 = 14
Step 3: divide → 48.0 ÷ 14 = 3.43 GPA
Semester GPA vs cumulative GPA
Semester GPA is calculated for one term only. Cumulative GPAincludes every course you've taken at your institution. To calculate cumulative GPA, apply the same formula to all courses across all semesters — not an average of semester GPAs.
Think of it this way: if you took 15 credits in fall (3.8 GPA) and 15 credits in spring (3.2 GPA), your cumulative GPA is not the average of 3.8 and 3.2. It's the total grade points from both semesters divided by total credits from both semesters.
Weighted vs unweighted GPA
Unweighted GPA uses the standard 4.0 scale for all courses. A B is always 3.0, whether it's in gym class or AP Chemistry.
Weighted GPA adds extra points for harder courses. The most common scale is 5.0:
| Grade | Regular class | Honours class | AP/IB class |
|---|---|---|---|
| A | 4.0 | 4.5 | 5.0 |
| B | 3.0 | 3.5 | 4.0 |
| C | 2.0 | 2.5 | 3.0 |
| D | 1.0 | 1.5 | 2.0 |
Most US colleges convert weighted GPAs to unweighted 4.0 scale during admissions evaluation. If your school only reports weighted GPA, colleges will do the unweighting themselves.
Grade point scales vary by school
Not every school uses the same grade point values. The most common variants:
| Grade | Standard 4.0 | 1/3-point (UF) | 0.3-point (Purdue) |
|---|---|---|---|
| A | 4.0 | 4.00 | 4.0 |
| A− | 3.67 | 3.67 | 3.7 |
| B+ | 3.33 | 3.33 | 3.3 |
| B | 3.0 | 3.00 | 3.0 |
Our International GPA Converter handles the most common variants. For exact school-specific scales (like UF's third-point system), use ourUF GPA Calculator,ASU GPA Calculator, orPurdue GPA Calculator.
What doesn't count in GPA?
- Pass/Fail courses — usually no grade points, just credit earned
- Withdrawn courses — W grades typically don't affect GPA
- Incomplete grades — I grades carry no points until resolved
- Physical education courses — some schools exclude these from GPA
Frequently asked questions
What is the GPA formula?+
GPA = total grade points ÷ total credit hours. Grade points for a course = grade point value × credit hours. Add up all grade points across every course, divide by total credit hours, and you have your GPA.
What counts as one credit hour?+
In the US, one credit hour typically represents one hour of classroom instruction per week over a 15–16 week semester, or roughly 2–3 hours of total work (including class, study, and assignments) per week. A typical full-time course load is 15–16 credit hours per semester.
Do all courses count the same in GPA?+
No. A 4-credit chemistry class contributes twice as much to your GPA as a 2-credit elective, because the grade points are weighted by credit hours. A B in a 4-credit class (3.0 × 4 = 12 grade points) pulls your GPA up more than a B in a 2-credit class (3.0 × 2 = 6 grade points).
Do Pass/Fail or S/U courses affect GPA?+
Typically no. Courses taken Pass/Fail, Satisfactory/Unsatisfactory, or Credit/No Credit usually carry credit hours but no grade points, so they are excluded from GPA calculations. However, they count toward total credits needed for graduation.
How do repeated courses affect GPA?+
This depends on your school's policy. Some schools replace the original grade with the new one in your GPA calculation (grade forgiveness). Others count both attempts. At UF, for example, repeated coursework is counted in the GPA as many times as grades are received — check your institution's repeat-coursework policy.
What is a weighted GPA?+
Weighted GPA gives extra grade points for harder courses. In a typical 5.0 weighted scale: A in a regular class = 4.0, A in an honours class = 4.5, A in an AP/IB class = 5.0. Colleges usually unweight GPA during admissions review to compare students fairly.