How to Calculate GPA
A practical, no-fluff walkthrough of the formula behind every grade point average.
The basic GPA formula
Grade point average is a single number that summarises your performance across multiple courses. The standard US version uses a 4.0 scale, where each letter grade is converted into grade points, multiplied by the credit hours of the course, and then averaged. The formula looks like this:
GPA = sum(grade points × credits) ÷ sum(credits)
The credit weighting is the part most people skip when they try to do it in their head. A four-credit class with an A counts more toward your GPA than a one-credit class with the same grade, because it represents more learning hours. That is also why GPAs change slowly once you have accumulated a lot of credits — each new course is one small slice of a growing pie.
You can follow along with the calculator below. Add your real courses, or use the example numbers in the next section.
Your grades stay in this browser tab while you use the calculator and are not sent to a server.
Converting letter grades to grade points
Most US schools use the same letter-to-points mapping, with small differences in whether plus and minus grades are recognised and how A+ is handled. The table below shows the common conversion used by this calculator.
| Letter | Percent | Grade Points |
|---|---|---|
| A / A+ | 93–100 | 4.0 |
| A− | 90–92 | 3.7 |
| B+ | 87–89 | 3.3 |
| B | 83–86 | 3.0 |
| B− | 80–82 | 2.7 |
| C+ | 77–79 | 2.3 |
| C | 73–76 | 2.0 |
| C− | 70–72 | 1.7 |
| D | 60–69 | 1.0 |
| F | Below 60 | 0.0 |
A handful of schools treat A+ as 4.3 rather than 4.0, and some do not use minus grades at all. If your school's grade scale uses different cutoffs or values, your calculated GPA will differ by a few hundredths of a point. Check your registrar's policy when precision matters.
A worked example
Imagine a semester with four courses:
- English 101, 3 credits, grade A → 4.0 × 3 = 12.0 quality points
- Calculus I, 4 credits, grade B → 3.0 × 4 = 12.0 quality points
- History 110, 3 credits, grade A− → 3.7 × 3 = 11.1 quality points
- Studio Art, 2 credits, grade B+ → 3.3 × 2 = 6.6 quality points
Total quality points = 12.0 + 12.0 + 11.1 + 6.6 = 41.7. Total credits = 3 + 4 + 3 + 2 = 12. GPA = 41.7 ÷ 12 ≈ 3.48. If you type those rows into the calculator above, you should see the same number.
Common questions
- Is a 3.5 GPA good?
- It is generally considered strong. What counts as good depends on your school, your major, and your goals — talk with your counselor or advisor about thresholds that apply to you.
- Does GPA include withdrawals?
- Usually no. Courses you withdraw from typically show up as W on the transcript and do not factor into the GPA, but specific rules vary by school.
- How is cumulative GPA different from semester GPA?
- Semester GPA only counts the term in question, while cumulative GPA averages every graded course you have ever taken at the school using the same credit-weighted formula.
- Why does my school's GPA differ from this one?
- Schools may use different grade-point mappings, treat plus and minus grades differently, or include or exclude specific course types. Always treat your official transcript as the source of truth.