A GPA is a weighted average of course grades, and every high school in the United States computes one, on at least two scales, with rules that differ from district to district on exactly the points that matter: what an A+ is worth, how much an Honors or AP course adds, and whether a half-credit course counts half. This page is the calculator (weighted and unweighted together), the method by hand, the tables, and the rules, with their sources.
Download the GPA sheet (PDF) (the letter-to-point tables for unweighted, Honors and AP, the worked example, a blank course table for your own transcript and the GPA-to-percentage table; two pages, free).
The calculator
How to calculate a GPA by hand
- Points for each grade. A and A+ are 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, F 0. (The College Board's BigFuture description of the 4.0 scale; the plus-minus steps are the ones in published district scales such as Buffalo's.)
- Multiply by credits. A full-year course is usually 1 credit, a semester course 0.5. Some schools count every course as 1.
- Add, and divide by the total credits. That is the unweighted GPA.
- For the weighted GPA, add the course's bonus to its points first: 0.5 for Honors, 1.0 for AP, IB and dual enrollment, on passing grades. These are the North Carolina State Board's quality points (since 2015-16) and the Alexandria City, Virginia scale; many districts use the same two numbers, some use only 1.0 for AP, some cap Honors at 4.5.
Worked example. Six courses in one year:
| Course | Level | Grade | Points | Weighted points | Credits |
|---|---|---|---|---|---|
| English 10 | Standard | A | 4.0 | 4.0 | 1.0 |
| AP Calculus AB | AP | B+ | 3.3 | 4.3 | 1.0 |
| Honors Chemistry | Honors | A- | 3.7 | 4.2 | 1.0 |
| US History | Standard | B | 3.0 | 3.0 | 1.0 |
| Spanish 3 | Standard | A | 4.0 | 4.0 | 1.0 |
| PE | Standard | A | 4.0 | 4.0 | 0.5 |
| Total | 20.00 | 21.50 | 5.5 |
Unweighted GPA = 20.00 / 5.5 = 3.64. Weighted GPA = 21.50 / 5.5 = 3.91. The half-credit PE course counts half; the B+ in AP Calculus is a 3.3 unweighted and a 4.3 weighted, which is above the unweighted A in English, and that is the whole point of weighting.
The tables
| Letter | Percentage (plus-minus scale) | Unweighted (4.0) | Honors (+0.5) | AP, IB, dual enrollment (+1.0) |
|---|---|---|---|---|
| A+ | 97-100 | 4.0 | 4.5 | 5.0 |
| A | 93-96 | 4.0 | 4.5 | 5.0 |
| A- | 90-92 | 3.7 | 4.2 | 4.7 |
| B+ | 87-89 | 3.3 | 3.8 | 4.3 |
| B | 83-86 | 3.0 | 3.5 | 4.0 |
| B- | 80-82 | 2.7 | 3.2 | 3.7 |
| C+ | 77-79 | 2.3 | 2.8 | 3.3 |
| C | 73-76 | 2.0 | 2.5 | 3.0 |
| C- | 70-72 | 1.7 | 2.2 | 2.7 |
| D+ | 67-69 | 1.3 | 1.8 | 2.3 |
| D | 65-66 | 1.0 | 1.5 | 2.0 |
| F | below 65 | 0.0 | 0.0 | 0.0 |
On the 10-point scale without pluses and minuses (North Carolina's state scale, and many others): 90 to 100 is an A, 4.0; 80 to 89 a B, 3.0; 70 to 79 a C, 2.0; 60 to 69 a D, 1.0; below 60 an F. The same Honors and AP bonuses apply.
Where schools differ: some give an A+ 4.3 (the calculator has a field for it); some apply the AP bonus only to grades of C+ and above (Alexandria City does, so a C- in an AP course is 1.7 on both scales); some weight only AP, not Honors; some do not weight at all and report class rank instead. The handbook's grading page has the school's own table, and it overrides this one.
GPA to percentage
The reverse question, "what percentage is a 3.5?", has no exact answer, because a GPA is an average of letters and each letter spans a range. The usual reading, from the plus-minus scale:
| GPA | Letter average | Percentage, roughly |
|---|---|---|
| 4.0 | A | 93-100 |
| 3.7 | A- | 90-92 |
| 3.5 | between A- and B+ | about 89-90 |
| 3.3 | B+ | 87-89 |
| 3.0 | B | 83-86 |
| 2.7 | B- | 80-82 |
| 2.3 | C+ | 77-79 |
| 2.0 | C | 73-76 |
| 1.7 | C- | 70-72 |
| 1.0 | D | 65-66 |
A weighted GPA does not convert to a percentage at all without the course list: a 4.3 weighted may be an A- average with many AP courses or a B+ average with more.
What colleges do with the two numbers
Most transcripts carry both GPAs and the course list, and many colleges recompute a GPA of their own from the transcript, on their own scale, sometimes from academic courses only. The College Board's advice is that the weighted system is the school's and colleges may apply their own weighting. In practice an admissions reader looks at the unweighted GPA for consistency, the weighted GPA and the course list for rigor, and the trend across years. The GPA scale page has what a 3.6, 3.8, 4.2 and 5.0 mean and what the Common App asks for.
The GPA across years
A single year's GPA is one term in the cumulative GPA, which is the number on the transcript. The cumulative GPA calculator combines years and shows what GPA is needed from here to reach a target. For the two scales side by side with their conversion, the weighted GPA calculator; for middle school, where credits are rare and the scale simpler, the middle school GPA calculator.
What the number is for, this term
A GPA moves slowly, which is the useful fact: by junior year, 1 credit out of 18 moves the cumulative GPA by at most 0.17 even from F to A. The number that can still move is this semester's grade in each course, and the course where a grade is one step below the next letter is where a term's effort pays. Run the calculator with next semester's expected grades, change one course by a step, and watch what it does; then spend the term on that course.
Download the GPA sheet (PDF) (the letter-to-point tables, the worked example, a blank course table and GPA to percentage; two pages, free).
Where to get help
A 1-on-1 online class with a tutor who holds a master's in mathematics and teaches the US curriculum, Algebra 1 to AP Calculus, chemistry and physics, at 7 am before school, after 4 pm and on weekend mornings, US time, for US$10 to $13 an hour: the grade worked out above read together in the free 30-minute first class, the category or the course where five more points cost least found, and the term spent on exactly that. How online tutoring from India to the USA works, or the 1-on-1 online tutoring page.
Questions parents ask
1How do you calculate a high school GPA?
2What is the difference between weighted and unweighted GPA?
3How do I convert a percentage to GPA?
4Do semester courses count the same as full-year courses?
5Is a 3.7 GPA good?
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