Understand your results
A percentage describes how much credit you earned. A grading scale converts that percentage into a label, such as A, B, or C. Your course sets the rules for that conversion.
An example A–F grading scale
The homepage starts with this editable example. It is not a universal US grading standard.
| Letter | Percentage range |
|---|---|
| A | 90% and above |
| B | 80% to below 90% |
| C | 70% to below 80% |
| D | 60% to below 70% |
| F | Below 60% |
Use the scale in your syllabus or grading policy. Some courses use plus/minus grades, different pass marks, standards-based ratings, or no letter grades at all.
Percentage first, letter second
A score of 17 out of 20 is 85%, regardless of the letter scale: 17 ÷ 20 × 100 = 85. On the example above, 85% is a B. If a course uses different boundaries, the same 85% can receive a different label.
Rounding can change a boundary result
Suppose an A starts at 90%. An unrounded score of 89.5% is below that threshold. If your teacher rounds to the nearest whole percentage before assigning letters, it becomes 90%. If the teacher uses the unrounded score, it remains below an A.
The grading calculator uses the unrounded percentage for letters by default. You can explicitly choose whole-number rounding. The two-decimal display is separate: a displayed 90.00% can still be just below 90% internally and receive a B under the unrounded rule.
How to set a custom scale
- Open “Scale and rounding settings” on the homepage calculator.
- Enter the minimum percentages for A, B, C, and D in descending order.
- Choose the letter-grade rounding rule used by your course.
- If your scale cannot be represented by these four thresholds, choose “Percentage only” and apply your course’s scale separately.
Partial credit, weights, and curves
For partial credit or questions with different values, calculate from points earned and points possible. For course categories such as homework and exams, use the weighted grade calculator. A curve or dropped-score policy changes how the underlying grade is determined; it is not automatically applied by choosing a letter scale.
Percentage grades are not GPA values
These tools do not convert percentages into an official GPA. GPA calculations can depend on course credits, institution-specific grade points, repeated-course rules, and other policies. Use the relevant school’s instructions for an official result.
See our methodology for the calculation formulas, or report an unclear result.