To calculate GPA, convert each letter grade to grade points (A = 4.0, B = 3.0, C = 2.0, D = 1.0, F = 0), multiply each by the course's credit hours to get quality points, add the quality points, and divide by the total credit hours. The result is a credit-weighted average on a 4.0 scale.
What is the GPA formula?
The formula used by most US high schools and colleges is:
GPA = ฮฃ (grade points ร credit hours) รท ฮฃ credit hours
Each course's grade points multiplied by its credits is called its quality points. A 4-credit course therefore counts four times as much as a 1-credit course. University registrars, such as the University of Toledo's, describe exactly this calculation: quality points per course, then total quality points divided by total quality hours.
How do letter grades convert to grade points?
The base scale is the same nearly everywhere. Plus and minus values are where schools differ. The table below shows one widely used university scale (University of Toledo). Some schools use 3.7 and 3.3 instead of 3.67 and 3.33, some give A+ a 4.0 or 4.33, and some do not use plus and minus grades at all.
| Letter grade | Grade points (common scale) |
|---|---|
| A | 4.00 |
| A- | 3.67 |
| B+ | 3.33 |
| B | 3.00 |
| B- | 2.67 |
| C+ | 2.33 |
| C | 2.00 |
| C- | 1.67 |
| D+ | 1.33 |
| D | 1.00 |
| D- | 0.67 |
| F | 0.00 |
If grades are recorded as percentages, College Board's general conversion maps 90โ100 to A (4.0), 80โ89 to B (3.0), and 70โ79 to C (2.0). The cutoffs for D and F vary more between schools, so the school's own grading policy should take priority.
How do you calculate GPA step by step?
Step 1: List each course with its credits and grade
Credits (also called credit hours or units) are on the transcript or course catalog. A typical college course is 3 or 4 credits; many high schools count a year-long course as 1 credit.
Step 2: Convert each grade to points
Use the school's scale. If unsure about plus and minus values, the registrar's website usually publishes it.
Step 3: Multiply points by credits
This gives quality points for each course.
Step 4: Divide total quality points by total credits
Courses that do not carry quality hours, such as pass/fail, withdrawals, or incompletes at many schools, are left out of both totals.
Worked example: a college semester GPA
| Course | Credits | Grade | Points | Quality points |
|---|---|---|---|---|
| Calculus | 3 | A | 4.00 | 12.00 |
| Chemistry with lab | 4 | B+ | 3.33 | 13.32 |
| English | 3 | B | 3.00 | 9.00 |
| Spanish | 2 | C+ | 2.33 | 4.66 |
| Seminar | 1 | A- | 3.67 | 3.67 |
| Total | 13 | 42.65 |
GPA = 42.65 รท 13 = 3.28 (rounded to two decimals).
A simple average of the five grade-point values would give 3.27, slightly different, because it ignores that the 4-credit chemistry course carries more weight than the 1-credit seminar. With larger credit differences, the gap between the two methods grows.
How do you calculate a weighted GPA?
A weighted GPA gives extra points for more demanding courses. College Board notes that some high schools award higher GPA points for AP and honors courses. A common pattern is:
- Honors: +0.5 (an A becomes 4.5)
- AP or IB: +1.0 (an A becomes 5.0)
- Regular courses: no change
These bonuses are set locally. For example, one public school district's 2025โ26 program of studies adds 1.0 for each year-long AP grade and 0.5 for each year-long honors grade, gives half those amounts for semester courses, and adds no weight to D or F grades. Other schools use different bonuses or cap the weighted scale.
Worked example: weighted vs unweighted
Five year-long high school courses, 1 credit each:
| Course | Grade | Unweighted | Weighted |
|---|---|---|---|
| AP Biology | A | 4.0 | 5.0 |
| Honors English | B | 3.0 | 3.5 |
| Geometry | A | 4.0 | 4.0 |
| History | B | 3.0 | 3.0 |
| AP Spanish | B | 3.0 | 4.0 |
| Average | 3.4 | 3.9 |
Unweighted GPA = 17 รท 5 = 3.4. Weighted GPA = 19.5 รท 5 = 3.9. If courses have different credit values, multiply each weighted point value by its credits, exactly as in the unweighted method.
College Board also notes that colleges may recalculate an applicant's GPA, sometimes removing weighting, to compare students from different schools on one scale.
How do you calculate cumulative GPA?
Cumulative GPA covers every term so far. Add all quality points from all terms and divide by all credit hours from all terms.
Example: a student has a 3.2 GPA over 45 credits and earns a 3.6 over 15 credits this semester.
- Prior quality points: 3.2 ร 45 = 144
- New quality points: 3.6 ร 15 = 54
- Cumulative GPA = (144 + 54) รท (45 + 15) = 198 รท 60 = 3.30
Averaging the two GPAs, (3.2 + 3.6) รท 2 = 3.40, overstates the result because the new semester has only a third as many credits as the earlier record.
How do you raise a GPA?
Because GPA is a credit-weighted average, a few points follow directly from the formula:
- High-credit courses move GPA the most. An A in a 4-credit course adds more quality points than an A in a 1-credit course.
- Early terms are easier to change than later ones. As total credits grow, each new semester shifts the cumulative GPA less.
- Repeat policies matter. Some schools replace a failed grade when a course is retaken; others average both attempts. The registrar's policy determines which applies.
To see what score a final exam needs in order to reach a target course grade, which in turn feeds into GPA, a final grade calculator does the reverse calculation.
Common GPA mistakes
- Ignoring credits. Averaging letter-grade points without credit weighting gives the wrong answer whenever course sizes differ.
- Using the wrong plus/minus scale. A B+ worth 3.3 at one school may be 3.33 at another; the difference is small but can change the second decimal.
- Including pass/fail courses. At most schools these do not count toward GPA.
- Mixing weighted and unweighted values. Applications often ask for one specifically; report the one requested.