How GPA is calculated
By Dexaloop · Updated 27 October 2026 · Checked against the sources listed below
A GPA (grade point average) is calculated by turning each letter grade into grade points, multiplying those points by the course's credit hours, adding the results, and dividing by the total credit hours. A 4-credit A therefore counts twice as much as a 2-credit A. The rest of this guide explains each step, the difference between weighted and unweighted GPA, why an A+ is 4.0 at some schools and 4.33 at others, and how to combine terms into a cumulative GPA.
The four steps
The University of Illinois registrar sets out the method in four steps, and almost every college and many high schools use the same idea:
- For each course, multiply the grade points for your grade by the credit hours. The result is called quality points.
- Add the quality points for all courses.
- Add the credit hours for all courses that count toward GPA (often called GPA hours).
- Divide total quality points by total GPA hours.
The reason credits matter is simple. A course that meets more often, or carries more work, should move your average more. The NCES High School Transcript Study does the same thing at high school level: its points "are weighted by the number of Carnegie credits earned," so a course with less instruction time counts for less.
Converting letters to points
On the common 4.0 scale, A is 4, B is 3, C is 2, D is 1 and F is 0. Schools that use plus and minus grades add steps in between. The table below shows two real published scales side by side.
| Grade | University of Illinois | Acadia University |
|---|---|---|
| A+ | 4.00 | 4.33 |
| A | 4.00 | 4.00 |
| A- | not listed on the GPA page | 3.67 |
| B+ | 3.33 | 3.33 |
| B | not listed on the GPA page | 3.00 |
| C- | 1.67 | not shown here |
| F | 0.00 | 0.00 |
Both scales put each plus or minus a third of a point away from the plain letter (3.33, 3.67 and so on). The real difference is at the top. At Illinois an A+ earns the same 4.00 as an A, so the A+ is an honor but does not lift the average. At Acadia an A+ earns 4.33, so it can pull a GPA above 4.0. Neither is wrong. You need the scale your own school publishes.
High school scales vary too. College Board's BigFuture notes that "some schools don't use pluses and minuses, and others have different grade cutoffs," so the same percentage can earn different letters at different schools.
Worked example: one semester
Here is a college semester with five courses on the Acadia style scale.
| Course | Credits | Grade | Points | Quality points |
|---|---|---|---|---|
| Biology | 4 | A- | 3.67 | 14.68 |
| Calculus | 4 | B+ | 3.33 | 13.32 |
| English | 3 | A | 4.00 | 12.00 |
| History | 3 | B | 3.00 | 9.00 |
| Art | 2 | A+ | 4.33 | 8.66 |
| Total | 16 | 57.66 |
GPA = 57.66 / 16 = 3.60.
Now run the same grades at a school where an A+ is worth 4.00. Art becomes 2 x 4.00 = 8.00 quality points, the total falls to 57.00, and the GPA is 57.00 / 16 = 3.56. One grade on a small course moved the result by four hundredths, which can matter for honors lists and scholarship cutoffs.
Notice also what would happen if you ignored credits and simply averaged the five grade points: (3.67 + 3.33 + 4.00 + 3.00 + 4.33) / 5 = 3.67. That overstates the GPA because the 2-credit A+ is treated as if it were as big as Calculus.
Weighted vs unweighted GPA
An unweighted GPA uses the plain scale for every class. The NCES transcript study is unweighted on purpose: it states that "no additional grade points were assigned" for AP, IB and other honors classes.
A weighted GPA adds a bonus for harder courses. North Carolina is a clear published example. Orange County Schools explains that the state weighting system adds 0.5 quality point for Honors courses and 1.0 quality point for AP and IB courses, and that students also receive "an unweighted GPA that reflects no additional weighting for advanced courses."
Take one high school term, each class worth one credit, using that North Carolina rule:
| Class | Grade | Unweighted | Weighted |
|---|---|---|---|
| AP Chemistry | B | 3.0 | 4.0 |
| Honors English | A | 4.0 | 4.5 |
| Geometry | A | 4.0 | 4.0 |
| Spanish | B | 3.0 | 3.0 |
| History | A | 4.0 | 4.0 |
| GPA | 3.6 | 3.9 |
Same student, same report card, two honest numbers. That is why a transcript often shows both, and why you should say which one you mean when you quote it. Colleges may also redo the sum. BigFuture says colleges may "adjust or remove weighting assigned to AP or honors" to compare applicants fairly.
Cumulative GPA
Your cumulative GPA covers every term so far. The correct way is to carry quality points and credits forward, not GPAs.
Suppose the first semester above (A+ at 4.00) gave 57.00 quality points over 16 credits, a 3.56. The second semester gives 36.00 quality points over 12 credits, a 3.00.
- Right: (57.00 + 36.00) / (16 + 12) = 93.00 / 28 = 3.3214, shown as 3.32.
- Wrong: (3.5625 + 3.00) / 2 = 3.28.
The shortcut undercounts the bigger first semester. It only works when every term has the same number of credits.
Also check how your school displays the result. Illinois says its transcript GPA shows two decimal places and "is truncated, not rounded." A 3.3876 would show as 3.38 there, not 3.39.
Grades that do not count
Some grades carry credit but no grade points. The NCES study leaves out ungraded courses "such as pass/fail and audited courses," and the Illinois example treats credit-only grades as having no GPA hours. Leave these out of both the quality points and the credits, or your GPA will come out too low.
Common mistakes
- Averaging letter grades without credits. A 1-credit lab and a 4-credit lecture are not equal.
- Using the wrong A+ value. Check whether your school uses 4.00 or 4.33.
- Mixing weighted and unweighted numbers. Do not add a weighted term to an unweighted one.
- Averaging semester GPAs. Use total quality points over total credits.
- Counting pass/fail credits in the divisor. They usually belong in neither total.
- Rounding up when the school truncates. A cutoff of 3.50 is not met by a 3.497.
Once you know your school's scale and which grades count, the sum takes a minute. The GPA calculator below does the multiplying and adding for you, and lets you switch between scales to see the difference.
Work out your GPA: tools.dexaloop.com/gpa-calculator/. Free, no sign-up, and it runs on your device.
Questions
Is an A+ worth 4.0 or 4.33?
It depends on the school. The University of Illinois counts an A+ as 4.00, the same as an A. Acadia University counts it as 4.33. Your school's catalog or registrar page lists the value it uses.
Do pass/fail classes count toward GPA?
Usually not. The NCES transcript study leaves pass/fail and audited courses out, and registrars such as Illinois show credit-only grades with no grade points. Check your own school's rules for how it treats them.
Can I average my semester GPAs to get my cumulative GPA?
Only if every semester has exactly the same number of credits. Otherwise add up all quality points from every term and divide by all GPA credits from every term.
Why is my GPA on a college application different from my transcript?
Colleges may recalculate it. College Board says some colleges adjust or remove the extra weight that high schools give to AP and honors classes so that applicants can be compared on the same basis.
Should I round or truncate my GPA?
Follow your school. The University of Illinois shows two decimal places and truncates, so 3.387 appears as 3.38, not 3.39.
Sources
- University of Illinois Office of the Registrar: Calculate your GPA
- College Board BigFuture: How to convert your GPA to a 4.0 scale
- NCES / The Nation's Report Card: Understanding the High School Transcript Study
- Acadia University Registrar: Grades
- Orange County Schools (North Carolina): Academic procedures, weighted and unweighted GPA
This guide is general information, not legal, tax or financial advice. Rules change; check the official source for your own case. Found a mistake? Email support@dexaloop.com.