If your school doesn't use credit hours, your GPA is usually calculated as a simple unweighted average of grade points — add up the grade points for every course and divide by the number of courses, rather than multiplying each grade by a credit value first and dividing by total credits.
Two different ways to average grades
Most US colleges and many high schools calculate GPA as a credit-weighted average: each course's grade points are multiplied by its credit hours, those products are summed, and the total is divided by the sum of credit hours. That's the formula behind the standard GPA calculation guide most students are taught.
But plenty of schools — including many that don't assign credit or unit values to individual courses, some international grading systems, and some K-12 report cards — skip that step entirely and use a simple average: every course counts equally, no matter how many hours it met per week or how heavy its workload was.
Credit-weighted GPA = Σ(Grade Points × Credit Hours) ÷ Σ(Credit Hours)
Simple average GPA = Σ(Grade Points) ÷ Number of Courses
The simple average is really just the credit-weighted formula with every course's "credit hours" set to 1 — every class gets the same vote.
Worked example: the same four courses, two different GPAs
Suppose a student took four courses in a term. To show exactly where the two methods diverge, here's what the same course list would look like under both approaches — first ignoring course weight entirely, then applying the credit-hour values these courses would typically carry at a school that does weight by credits.
Grade points earned per course
| Course | Grade | Grade Points | Typical Credit Hours |
|---|---|---|---|
| Calculus | A | 4.0 | 5 |
| Chemistry | B+ | 3.3 | 4 |
| History | A- | 3.7 | 3 |
| Art | C | 2.0 | 1 |
Simple average (no credit hours):
Total grade points: 4.0 + 3.3 + 3.7 + 2.0 = 13.0
GPA = 13.0 ÷ 4 = 3.25
Credit-weighted average (same grades, hours applied):
Quality points: (5 × 4.0) + (4 × 3.3) + (3 × 3.7) + (1 × 2.0) = 20.0 + 13.2 + 11.1 + 2.0 = 46.3
Total credits: 5 + 4 + 3 + 1 = 13
GPA = 46.3 ÷ 13 = 3.56
Why the two numbers diverge
The gap here — 3.25 versus 3.56 — comes entirely from where the C landed. In the credit-weighted version, the C is in the lightest course (1 credit), so it barely drags the total down; the heavy A in Calculus (5 credits) dominates instead. In the simple average, every course counts identically, so that same C pulls just as hard on the final number as the A does — nothing about "how much" that course was supposed to count changes its influence.
The two methods only produce identical results when every course is roughly the same size or workload. The more uneven your course load, the more the two numbers can diverge — which is exactly why it matters to know which method your school actually uses before comparing your GPA to a friend's at a different institution.
What this means for you
- Don't assume your school weights by credit hours just because that's the more commonly discussed method. If your transcript or course catalog never lists a credit or unit value, a simple average is more likely.
- A simple average rewards consistency over course load. Since every class counts the same, there's no advantage to "loading up" grade points in a bigger course — every grade matters equally.
- This also affects how much a single bad grade can hurt you. Under a simple average, a C in even your lightest, least-important course drags your GPA exactly as much as a C in your most demanding one would.
Try it yourself
If your school uses a simple, non-credit-weighted average, our GPA Calculator can still handle it — just enter each course with an equal credit value (like 1) for every class, which effectively turns the credit-weighted formula into a plain average. If your school does use credit hours, see our guide on how credit hours affect your GPA for the weighted version of this same math.
