The US grading system uses letter grades from A to F: A is excellent, B good, C average, D poor but often still passing, and F failing (there is no E). Each letter covers a range of percentages, usually A = 90–100%, B = 80–89%, C = 70–79%, D = 60–69%, F = below 60%, and is converted into grade points on a 4.0 scale to calculate a GPA. There is no national standard, so the exact cutoffs and point values come from each school.
What do the US letter grades mean?
Many schools also add plus and minus grades, which split each letter into three steps. Here is one real scale, from Sacred Heart University’s undergraduate grading policy, next to the simple 10-point scale described by College Board:
| Letter | Plus/minus scale (Sacred Heart) | Simple scale | Grade points (common 4.0 scale) | Grade points (Sacred Heart) |
|---|---|---|---|---|
| A | 93–100% | 90–100% | 4.0 | 4.00 |
| A- | 90–92% | — | 3.7 | 3.67 |
| B+ | 87–89% | — | 3.3 | 3.33 |
| B | 83–86% | 80–89% | 3.0 | 3.00 |
| B- | 80–82% | — | 2.7 | 2.67 |
| C+ | 77–79% | — | 2.3 | 2.33 |
| C | 73–76% | 70–79% | 2.0 | 2.00 |
| C- | 70–72% | — | 1.7 | 1.67 |
| D+ | 67–69% | — | 1.3 | 1.33 |
| D | 60–66% | 60–69% | 1.0 | 1.00 |
| F | 0–59% | below 60% | 0.0 | 0.00 |
Some schools also give an A+ (often still worth 4.0, though some schools give more) and a D-. Others, like the undergraduate programs at Case Western Reserve University, use only A, B, C, D and F without plus or minus.
What percentage do you need for each grade?
The cutoffs are the part that varies most. Three things to check on your syllabus or school website:
- Where an A starts. On a simple scale 90% is an A. On a plus/minus scale 90% is often an A-, and a full A needs 93%.
- Where failing starts. The most common line is 60%, but College Board notes that some schools fail anything below 65% and put D at 66–69%.
- Rounding. Some teachers round 89.5% up to 90%, others do not. The grade calculator gives the letter for your exact percentage and lets you switch between a plus/minus and a simple scale.
If your class grade is a weighted average of homework, quizzes and exams, the percentage in this table is that weighted result, not the average of your test scores.
How do letter grades become a GPA?
Each letter has a grade-point value. A GPA is the average of those points, weighted by how many credits each course is worth:
GPA = sum of (grade points × credits) ÷ total credits
Take three courses: A- (3 credits), A- (3 credits) and B (4 credits).
| Scale | Calculation | GPA |
|---|---|---|
| Common 4.0 scale (A- = 3.7) | (3.7 × 3 + 3.7 × 3 + 3.0 × 4) ÷ 10 = 34.2 ÷ 10 | 3.42 |
| Sacred Heart scale (A- = 3.67) | (3.67 × 3 + 3.67 × 3 + 3.00 × 4) ÷ 10 = 34.02 ÷ 10 | 3.40 |
The same transcript gives slightly different GPAs, so always compare numbers calculated on the same scale. The GPA calculator does this sum for any list of courses, and the guide what is GPA walks through cumulative and semester GPA in more detail.
What is a credit hour?
Credits are what make some courses count more than others. For US colleges, federal rules (34 CFR 600.2) let each institution define its credit hour, but tie it to a baseline: roughly one hour of class and at least two hours of work outside class per week, for about 15 weeks, for one semester credit hour (10–12 weeks for a quarter hour). A typical three-credit college course therefore means about three hours in class each week.
High schools often count courses as full-year or half-year credits instead, but the principle in a GPA is the same: bigger courses weigh more.
What do P, W, I and other transcript symbols mean?
Not every course ends with a letter grade. These symbols are common, though the exact rules belong to each school:
| Symbol | Meaning | Counted in GPA? |
|---|---|---|
| P / NP | Pass / no pass, for courses taken pass-fail | No |
| W | Withdrew from the course within the allowed period | No |
| I | Incomplete; the work must be finished by a deadline | No, until it becomes a letter |
| AU (Audit) | Attended for no credit | No |
| F | Failed | Yes, as 0.0 |
At Sacred Heart University, P/NP, W, I, audit and NG grades are not calculated in the GPA, and an I that is not completed by the deadline becomes an F. In other words, an incomplete is a delay, not a way to skip a grade. Schools also set their own limits on which courses may be taken pass-fail, so check the policy before choosing that option.
How is high school grading different?
US high schools use the same A–F letters, but two things often differ from college:
- Weighted GPA. Many high schools add a bonus for harder courses, typically +0.5 for honors and +1.0 for AP or IB, so a weighted GPA can go above 4.0. The unweighted GPA stays on the plain 4.0 scale.
- Recalculation by colleges. College Board explains that colleges often recalculate an applicant’s GPA, for example counting only core subjects (English, math, science, social studies, world languages) and changing the honors and AP bonus.
For how GPAs compare between students and colleges, see what is a good GPA.
How do grades from other countries convert to the US system?
There is no official conversion table. The US Department of Education states that there is no single authority in the United States for recognizing foreign qualifications: the college you apply to, the employer or the state licensing board decides, and many of them rely on independent credential evaluation services.
This matters because grading cultures differ. A mark that is excellent in one country may sit in the middle of a scale in another, so a simple percentage-for-percentage conversion can understate or overstate your results. If a US school asks for a GPA, check whether it wants a specific evaluation service, or calculates the GPA itself from your transcript.
Sources
- Sacred Heart University, Grading Policy (undergraduate grades, quality points, other grades): https://www.sacredheart.edu/offices—departments-directory/registrar/grading-policy/
- Case Western Reserve University, Grading and Transcript Keys: https://case.edu/registrar/grading-transcripts/grading-and-transcript-keys
- College Board BigFuture, “How to Convert Your GPA to a 4.0 Scale”: https://bigfuture.collegeboard.org/plan-for-college/get-started/how-to-calculate-gpa-4.0-scale
- 34 CFR 600.2, definition of credit hour: https://www.law.cornell.edu/cfr/text/34/600.2
- 34 CFR 668.34, Satisfactory academic progress: https://www.ecfr.gov/current/title-34/subtitle-B/chapter-VI/part-668/subpart-C/section-668.34
- U.S. Department of Education (USNEI), Recognition of Foreign Qualifications: https://www2.ed.gov/about/offices/list/ous/international/usnei/us/edlite-visitus-forrecog.html