On the standard U.S. GPA scale, an A is worth 4.0 points, a B 3.0, a C 2.0, a D 1.0 and an F 0. Plus and minus grades move a letter by about 0.3, so a B+ is 3.3 and an A- is 3.7. Weighted scales for Honors and AP classes add a bonus and usually top out at 5.0.
That’s the scale most American high schools and colleges start from. They don’t all finish in the same place, and the differences (what an A+ is worth, where a B ends, whether minus grades exist, how much an AP class adds) are exactly what makes two 3.7s from two schools hard to compare. The charts below are the full version.
The 4.0 GPA scale chart
This is the plus/minus scale GradeDuck’s calculators use. It’s the most common version in the U.S., and the percentage bands match the ones the College Board uses when it asks PSAT takers for their grade average (A+ is 97–100, A is 93–96, A- is 90–92).
| Letter grade | Percent | GPA points (4.0 scale) |
|---|---|---|
| A+ | 97–100 | 4.0 |
| A | 93–96 | 4.0 |
| A- | 90–92 | 3.7 |
| B+ | 87–89 | 3.3 |
| B | 83–86 | 3.0 |
| B- | 80–82 | 2.7 |
| C+ | 77–79 | 2.3 |
| C | 73–76 | 2.0 |
| C- | 70–72 | 1.7 |
| D+ | 67–69 | 1.3 |
| D | 65–66 | 1.0 |
| F | below 65 | 0.0 |
Some colleges also give a D- (0.7). Cornell’s ILR School and Indiana University both list one. Others drop it, so a 63 goes straight to F.
The points matter more than the percentages. Your GPA is built from the letter on your report card, not from the raw score. If your school calls an 88 a B+, that class is 3.3 points no matter what this chart says about 88.
Not every school draws the lines at the same percent
The percent column is the least standardized part of the whole system. Three published versions show how much it moves:
| Letter | Plus/minus scale (above) | College Board BigFuture chart | NAEP High School Transcript Study |
|---|---|---|---|
| A | 93–100 | 90–100 | 90–100 |
| B | 83–86 | 80–89 | 80–89 |
| C | 73–76 | 70–79 | 70–79 |
| D | 65–66 | 66–69 | 60–69 |
| F | below 65 | below 65 | below 60 |
The College Board’s BigFuture conversion page uses whole letters only, with no plus or minus. The federal High School Transcript Study, which reads real transcripts for its national GPA figures, converts numeric grades on a 10-point scale where a D runs all the way down to 60, unless a school’s own documents say otherwise. That’s the conversion the National Center for Education Statistics publishes for the study.
So a 91 can be an A at one school and an A- at another. That’s 4.0 points versus 3.7 for the same work. To find the letter for any score, or the percent range behind a GPA, use the GPA to percentage converter.
Plus and minus: 0.3 or 0.33?
Most schools step plus and minus grades by 0.3: A- is 3.7, B+ is 3.3. A smaller group works in thirds. The University of Texas at Austin, for example, lists an A- as 3.67 and a B+ as 3.33.
Over a full transcript the gap is small, usually a few hundredths. It still shows up when you check your own math against your registrar’s, so look at your school’s catalog before assuming 3.7.
And some systems ignore plus and minus entirely. The University of California’s admissions GPA counts an A- as a plain A (4 points) and a B+ as a plain B (3 points).
Is an A+ worth 4.0 or 4.3?
It depends on the school, and both answers are common among colleges:
| Who | A+ worth |
|---|---|
| GradeDuck’s default scale | 4.0 |
| Indiana University | 4.0 |
| Medical school applications (AMCAS) | 4.0 |
| Cornell (ILR School) | 4.3 |
| Law school applications (LSAC) | 4.33 |
On a 4.0-capped scale an A+ is a nice letter with no extra points. On a 4.3 scale it can push an unweighted GPA above 4.0, with no Honors or AP bonus involved. The AAMC, which runs the medical school application, says it gives A+ and A the same 4.0 weight. LSAC, which processes law school applications, converts an A+ to 4.33 on its own standard scale. Same transcript, two different readings of the top grade. The law school GPA calculator uses LSAC’s table.
Weighted GPA scales: 4.5, 5.0 and beyond
High schools that weight GPAs add a bonus for harder classes. The most common version adds 0.5 for Honors and 1.0 for AP or IB, which gives this chart:
| Letter | Regular | Honors (+0.5) | AP / IB (+1.0) |
|---|---|---|---|
| A / A+ | 4.0 | 4.5 | 5.0 |
| A- | 3.7 | 4.2 | 4.7 |
| B+ | 3.3 | 3.8 | 4.3 |
| B | 3.0 | 3.5 | 4.0 |
| B- | 2.7 | 3.2 | 3.7 |
| C+ | 2.3 | 2.8 | 3.3 |
| C | 2.0 | 2.5 | 3.0 |
| C- | 1.7 | 2.2 | 2.7 |
| D+ | 1.3 | 1.8 | 2.3 |
| D | 1.0 | 1.5 | 2.0 |
| F | 0.0 | 0.0 | 0.0 |
An F gets no bonus at all. That’s the usual rule, and it’s how the weighted GPA calculator works.
Districts set their own weights, though, and some go further. Chicago Public Schools’ board policy gives a regular A 4 points, an Honors A 5 and an AP or IB A 6, while a D is worth 1 point at every level. Under that system a weighted GPA can reach 6.0. If you’re new to weighting, weighted vs. unweighted GPA walks through a full schedule both ways.
Other scales you might run into
A 5.0 scale for every class. MIT’s registrar uses A = 5, B = 4, C = 3, D = 2 and F = 0, with no weighting involved. If an MIT transcript has no F’s, subtracting 1 gives the 4.0 equivalent: a 4.6 at MIT is a 3.6 elsewhere. With an F in the mix, that shortcut stops working, because the F is 0 on both scales.
A 100-point scale. Some high schools report a numeric average (say, 91.4) instead of a GPA. To turn it into points, convert each class’s percent to a letter first, then average the points. Converting the overall average in one step can land on a different letter than the class-by-class result.
Why GPA scales differ between schools
There’s no national rulebook. Grading policy in the U.S. is set locally, by district boards for public high schools and by faculty and registrars at colleges. That’s why the Chicago policy above can define a 6-point AP A while a district next door uses 5.0, and why Cornell’s ILR School can count an A+ as 4.3 while Indiana University counts it as 4.0.
The College Board says it plainly on its GPA page: your school may calculate GPA differently, some schools skip pluses and minuses, and others use different grade cutoffs.
How colleges put every applicant on one scale
Because the inputs vary so much, many colleges recalculate. According to the College Board, a college may drop noncore classes, focus on core academic subjects, or remove Honors and AP weighting to compare applicants evenly.
The University of California publishes its exact method, and it’s a good model of what normalizing looks like:
- Only A-G college-prep classes from the summer after 9th grade through the summer after 11th grade count.
- A = 4, B = 3, C = 2, D = 1. Pluses and minuses don’t count.
- Each semester of a UC-approved Honors-level class earns one extra point, up to 8 points total and no more than 4 from 10th grade. A D or F earns no extra point.
- The result isn’t rounded up or down.
Here’s how much the scale alone can change a number. Take four equal-credit classes with grades of A+, A-, A- and B+:
| Scale | Points | GPA |
|---|---|---|
| Plus/minus, A+ = 4.0 (GradeDuck default) | 4.0 + 3.7 + 3.7 + 3.3 | 3.68 |
| Plus/minus, A+ = 4.3 (Cornell-style) | 4.3 + 3.7 + 3.7 + 3.3 | 3.75 |
| Plus and minus ignored (UC-style) | 4 + 4 + 4 + 3 | 3.75 |
Same four grades. A seven-hundredths spread before anyone adds a weighting bonus.
The practical takeaway: report your GPA exactly as your transcript shows it, and know the scale it was built on. If an application asks for a GPA on a different scale, build it from your letter grades with the GPA calculator instead of converting the final number. And if you’re wondering what the top of the scale really takes, what is a 4.0 GPA covers it.