GPA Calculator
Enter your letter grades and the credit hours each course carries. The calculator converts every grade to quality points, weights it by credits, and reports the term GPA. Add your prior quality points and credit hours to get the cumulative figure as well.
Quality points are the thing that adds up
A grade point average is a weighted mean, and almost every mistake people make with it comes from forgetting the weights. Courses are not equal: a four-credit lecture counts more than a one-credit seminar, and a semester of sixty credits behind you counts vastly more than the three in front of you. The arithmetic is simple and the weighting is where it goes wrong.
This calculator converts each letter to a grade point on the scale you choose, multiplies by the course's credit hours to get quality points, and divides the total by total credits. Add a prior record and it does the same sum across both, and shows you what averaging the two GPAs would have given instead — because that shortcut is the single most common error in the whole calculation.
The number a transcript carries forward is not the GPA but the pair behind it: total quality points and total credit hours. A GPA is what you get when you divide one by the other, and it cannot be added, averaged or combined with another GPA directly. Only the two totals combine.
This is why a strong term moves a cumulative GPA so little. Fifteen credits of perfect work added to ninety credits of solid work shifts the average by a fraction, because the new work is a seventh of the total. The effect is entirely predictable from the weights and is routinely surprising anyway.
It is also why the calculation is worth doing before registration rather than after results. Knowing how much a given term can move the cumulative figure tells you whether a target is reachable in one term, in two, or not at all.
How to use this calculator
- List your grades Comma-separated letters, in any order: A, B+, C. Use the minus sign or a hyphen — both are accepted. Every letter must exist on the scale you select, so a plus or minus on a whole-letter scale will be rejected rather than silently rounded.
- List the credit hours in the same order One number per grade, matching position for position. A mismatch in length is rejected with both counts named, because a silently truncated list would produce a plausible and wrong answer.
- Add your prior record, if you want the cumulative figure Prior quality points and prior credit hours, both from your transcript. If it prints only a GPA and a credit total, multiply them to get the quality points. Leave both blank for the term GPA alone.
- Choose the scale Plus/minus awards 3.7 for an A− and 3.3 for a B+; whole letters award 4.0, 3.0, 2.0 and so on with nothing between. Which one applies is your institution's decision and it is printed on the transcript key.
The formula, and where it comes from
GPA = Σ(grade points × credit hours) ÷ Σ(credit hours)
Each course contributes its grade point multiplied by its credit hours — its quality points. The numerator is the sum of those contributions and the denominator is the sum of the credits. That is the entire calculation, and the weighting is the multiplication.
For a cumulative figure both sums extend across every term: prior quality points plus this term's, over prior credits plus this term's. Nothing about the formula changes; the sums simply run over more courses.
What the formula does not permit is averaging two GPAs. (a/b + c/d) ÷ 2 is not (a + c) ÷ (b + d) unless b and d are equal, and across a prior record and a single term they never are.
What each input means
- gᵢ Letter grade for course i — form field “Grades (comma-separated)”
- A letter on the selected scale. Converted to a grade point by the scale's table; an unrecognised letter is reported by name rather than skipped.
- cᵢ Credit hours for course i — form field “Credit hours, in the same order”
- The weight the course carries. Must be positive. Institutions differ on whether a laboratory or a half-semester course counts as a whole credit, and the transcript is authoritative.
- Qₚ Prior quality points — form field “Prior quality points (optional)”
- The accumulated numerator from earlier terms. Optional; supply it together with prior credits to get a cumulative GPA.
- Cₚ Prior credit hours — form field “Prior credit hours (optional)”
- The accumulated denominator from earlier terms. Optional, and only meaningful alongside prior quality points.
Worked examples
Every number below is produced by the same calculation engine the tool above runs. Nothing here is typed by hand, so the walkthrough cannot drift from what you get when you enter the same values yourself.
A three-course term
An A in a three-credit course, a B+ in a four-credit course and a C in a three-credit course. The four-credit course is the one carrying the most weight, and it is not the best grade.
Inputs Grades (comma-separated) = A, B+, C, Credit hours, in the same order = 3, 4, 3, Prior quality points (optional) = , Prior credit hours (optional) = , Grading scale = plus-minus
- Scale US 4.0 with plus/minus
- Quality points per course A × 3 credit(s) = 12; B+ × 4 credit(s) = 13.2; C × 3 credit(s) = 6
- Totals 31.2 quality points over 10 credit hours
- Term GPA 31.2 ÷ 10 = 3.12
Result Term GPA 3.12
Quality points run 4.0 × 3 = 12, 3.3 × 4 = 13.2 and 2.0 × 3 = 6, for 31.2 over 10 credit hours — a term GPA of 3.12.
The unweighted average of 4.0, 3.3 and 2.0 is 3.1, which is close enough here to hide the point. The agreement is a coincidence of these particular credits; shift the A to the four-credit slot and the weighted figure moves to 3.19 while the unweighted average does not move at all.
One excellent course against a long record
A student with 180 quality points over 60 credit hours — a 3.0 cumulative — takes a single three-credit course and earns an A.
Inputs Grades (comma-separated) = A, Credit hours, in the same order = 3, Prior quality points (optional) = 180, Prior credit hours (optional) = 60, Grading scale = plus-minus
- Scale US 4.0 with plus/minus
- Quality points per course A × 3 credit(s) = 12
- Totals 12 quality points over 3 credit hours
- Term GPA 12 ÷ 3 = 4
- Prior record 180 quality points over 60 credit hours (prior GPA 3)
- Cumulative (12 + 180) ÷ (3 + 60) = 192 ÷ 63 = 3.04762
- Why not the average of the two Averaging the two GPAs would give 3.5. That treats a 3-credit term as equal in weight to 60 credits, which it is not.
Result Term GPA 4; cumulative 3.04762
The term GPA is 4.0 and the cumulative moves from 3.00 to 3.05. Three credits against sixty is a twentieth of the record, and the arithmetic pays out accordingly.
The working also prints what averaging the two GPAs would have given: 3.5. That figure is wrong by nearly half a point and it is the number a student reaches for when planning, which is precisely why it is shown beside the correct one rather than left unmentioned.
Reading the result
Term GPA
The weighted average of this term alone. It is the figure that determines term honours and academic standing at most institutions, and it moves freely because the denominator is small.
Cumulative GPA
The weighted average across everything, computed from the two running totals rather than from the two averages. This is the figure on the transcript and the one that appears on applications.
The comparison line
When a prior record is supplied the working prints what averaging the two GPAs would have produced. It is there to be disbelieved and then checked: the gap between it and the correct figure is the size of the error being avoided.
When you would use this
Planning a term before registration
Entering hypothetical grades against the credits you intend to take shows what a term can and cannot do to the cumulative figure. A student trying to lift a 2.8 to a 3.0 usually discovers it takes more than one term.
Assumptions and limitations
What this calculator assumes
- Every course counts towards the average. Institutions commonly exclude transfer credits, pass/fail courses and repeated-course originals, and none of those exclusions is modelled here.
- The grade-point table is your institution's. The two offered are the widely used North American scales; where an institution awards 4.3 for an A+ or uses a different table entirely, the transcript key governs.
Where it stops being the right tool
- Repeated courses are not handled. Grade replacement and grade forgiveness policies change which attempt enters the average, and the rule varies by institution.
- Weighted high-school GPAs, where an honours or advanced course adds a point, are outside the two scales offered.
- It does not convert between national systems. A GPA and a percentage or a foreign grade are related by an admissions policy rather than by arithmetic.
Common mistakes
Averaging a term GPA with a cumulative GPA
Why it happens. Both are averages of the same kind of thing, so averaging them looks like the natural next step.
How to avoid it. Combine the totals, not the averages. Add quality points to quality points and credits to credits, then divide once at the end.
Entering grades and credits in different orders
Why it happens. The two lists are typed separately and it is easy to reorder one while editing.
How to avoid it. The tool rejects a length mismatch, but it cannot detect a reordering of equal length. Read the per-course quality points in the working — a course whose grade and credits are mismatched usually looks obviously wrong there.
Frequently asked questions
How do I calculate my cumulative GPA?
Add this term's quality points to your prior quality points, add this term's credits to your prior credits, and divide. Entering the prior pair here does exactly that and shows both sums.
What is a quality point?
A grade point multiplied by the credit hours of its course. Quality points are what accumulate on a transcript; the GPA is their total divided by total credits.
Why did my GPA barely move after a perfect term?
Because the term is a small share of the total credits. Fifteen credits added to ninety is a sixth of the record, and the average moves by roughly a sixth of the gap.