A letter grade is a symbol, usually A, B, C, D or F, that summarizes how well a student performed in an assignment or course.
A means excellent work, B good, C satisfactory, D passing but weak, and F failing. Many schools add plus and minus signs for finer steps.
From percent to letter
Teachers usually grade in percentages first, then convert. The most common US conversion is the 10-point scale:
| Percent | Letter | GPA points |
|---|---|---|
| 90-100 | A | 4 |
| 80-89 | B | 3 |
| 70-79 | C | 2 |
| 60-69 | D | 1 |
| Below 60 | F | 0 |
So an 87.4% in English is a B, which becomes 3 points in your GPA. Not every school uses these cutoffs. Some states set a statewide scale, and our grading scale page lists them, including state-specific versions such as Florida’s and North Carolina’s.
What happens at the boundary
Rounding rules decide close calls. If a teacher rounds to the nearest whole percent, an 89.5 becomes 90 and an A. If the gradebook truncates, it stays an 89 and a B. Ask early in the term which rule your teacher uses. The grade calculator shows your exact percentage before any rounding.
Letters aren’t the only system
Some schools replace letters with proficiency levels tied to specific skills. That approach is called standards-based grading, and it reads very differently on a report card. Others split letters further with plus/minus grading.