How to calculate a test grade
Divide the points you earned by the total points possible, then multiply by 100 to get a percentage.
grade % = points earned ÷ total points × 100
Example: you scored 42 out of 50.
42 ÷ 50 = 0.84. 0.84 × 100 = 84%, which is a B on the standard scale.
You missed 8 points. To get an A− (90%), you'd have needed 45 points.
If you know how many questions you got wrong, subtract that from the total first. Missing 6 questions out of 40 means 34 right: 34 ÷ 40 = 85%.
Letter grade scale
This is the most common scale in US schools and colleges. Your school may use a different one, so check your syllabus.
| Letter | Percentage | GPA points |
|---|---|---|
| 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 | 63–66% | 1.0 |
| D− | 60–62% | 0.7 |
| F | Below 60% | 0.0 |
Want to turn your letter grades into a GPA? Use the GPA calculator.
Tests worth different points
If tests have different totals, don't average the percentages. Add up all the points you earned and divide by all the points possible. For example, 18/20 on a quiz (90%) and 60/100 on an exam (60%) is 78 out of 120 = 65%, not the 75% you'd get by averaging the two percentages. The bigger test counts for more.
If your teacher weights categories instead (for example, homework 20%, tests 50%, final 30%), multiply each category's percentage by its weight and add the results.
Frequently asked questions
Is 89.5% rounded up to an A−?
That depends on your teacher or school. Many round to the nearest whole number, which would make 89.5% a 90%. This calculator doesn't round, so 89.5% shows as a B+.
Can I enter extra credit?
Yes. Include extra credit in your points earned. If you score more than the total, the percentage will be over 100%.
What's a passing grade?
On the standard US scale, 60% (D−) is usually the lowest passing grade. Many courses or programs require a C (73%) or higher to count toward a degree or as a prerequisite.
Last reviewed November 2026.