How the 4.0 scale works
GPA is a credit-weighted average of your grades converted to points. Every letter grade maps to a number — A is 4.0, and each step down (A to A-, A- to B+) subtracts 0.3, until F at 0. Each course contributes its points multiplied by its credit hours ("quality points"), and your GPA is total quality points divided by total credits. The defaults above — an A and a B+ at 3 credits each, an A- at 4 credits, and a 1-credit A — work out to (12.0 + 9.9 + 14.8 + 4.0) ÷ 11 = 3.70.
Letter grade to grade point conversion
| Letter | Grade points | Typical percent |
|---|---|---|
| A+ / A | 4.0 | 93–100 |
| A- | 3.7 | 90–92 |
| B+ | 3.3 | 87–89 |
| B | 3.0 | 83–86 |
| B- | 2.7 | 80–82 |
| C+ | 2.3 | 77–79 |
| C | 2.0 | 73–76 |
| C- | 1.7 | 70–72 |
| D+ | 1.3 | 67–69 |
| D | 1.0 | 63–66 |
| D- | 0.7 | 60–62 |
| F | 0.0 | Below 60 |
Why credits change everything
Students often estimate their GPA by eyeballing their letter grades — "mostly A's, a couple of B's, so around 3.7." The eyeball method fails because it ignores credits. A B in a 4-credit organic chemistry course pulls your GPA down as much as B's in four separate 1-credit seminars. When you're deciding where to spend limited study time in finals week, the credit-weighted view is the honest one: protecting the grade in your highest-credit course is usually worth more GPA than perfecting a light elective.
Semester GPA vs. cumulative GPA
This calculator computes the GPA of whatever courses you enter — one semester's worth or your whole transcript. For a cumulative GPA across semesters, you can either enter every course, or treat each past semester as one row: its credits are the semester's total credits, and you'd need its exact GPA rather than a letter. Because letters round to 0.3 steps, entering full transcripts course-by-course is more accurate. Repeated courses follow your school's replacement policy — some replace the old grade entirely, others average the attempts — so the transcript, not any calculator, is the final word.
Frequently asked questions
How is GPA calculated?
Each letter grade converts to grade points (A = 4.0, B = 3.0, C = 2.0, D = 1.0, F = 0, with +/− steps of 0.3). Multiply each course's points by its credit hours, add them up, and divide by total credit hours. Three credits of A and three credits of B = (4.0×3 + 3.0×3) ÷ 6 = 3.5.
Is an A+ worth more than an A?
At most US schools, no — both are 4.0, so the scale caps there. A minority of institutions award 4.3 for an A+; if yours does, your official GPA will run slightly higher than this calculator shows for A+ grades.
Do credit hours really matter that much?
Yes. A grade in a 4-credit course moves your GPA twice as much as the same grade in a 2-credit course. This is why a low grade in a high-credit science course with lab is so costly, and why 1-credit electives barely register.
What GPA do I need for honors?
Common thresholds: 3.5 for Dean's List at many colleges, 3.5 for cum laude, 3.7 for magna cum laude, and 3.9 for summa cum laude — but every institution sets its own cutoffs and some use class rank instead. Check your school's academic catalog.