Letter Grade Calculator
Convert a percentage score into a letter grade.
| Range | Grade |
|---|
Convert a percentage score into a letter grade (A+ through F) using a standard grading scale, with the full scale shown for reference.
How to convert a test score to a letter grade
- Find your percentage: points earned ÷ points possible × 100.
- Look up the percentage on the grading scale to get the letter.
The calculator above does step 2 instantly. For step 1, any score works the same way, whether it's questions on a quiz or points on an assignment.
Examples
| Score | Percentage | Letter grade |
|---|---|---|
| 45 out of 50 | 90% | A− |
| 18.5 out of 20 | 92.5% | A− |
| 14 out of 18 | 77.8% | C+ |
| 18 out of 25 | 72% | C− |
| 35 out of 50 | 70% | C− |
| 31 out of 46 | 67.4% | D+ |
Letter grades and GPA points
Most US schools turn letter grades into grade points on a 4.0 scale to calculate a GPA. A common conversion is: A+ and A = 4.0, A− = 3.7, B+ = 3.3, B = 3.0, B− = 2.7, C+ = 2.3, C = 2.0, C− = 1.7, D+ = 1.3, D = 1.0, D− = 0.7 and F = 0. Some schools give an A+ 4.3, so check your school's policy. To average several courses by credit hours, use the GPA Calculator.
Why plus and minus grades matter
The difference between a B+ and a B− is a full 0.6 grade points on that scale. Over a semester of several classes, a few plus or minus grades can move a GPA noticeably, which is why it's worth knowing exactly where the cut-offs fall — a 79.6% is a C+, but 80% is a B−.
Frequently asked questions
Does every school use this exact scale?
No — grading scales vary by school, country, and even individual instructor. This uses a commonly published US-style scale as a general reference; check your syllabus for the scale that actually applies to your grade.
How do I turn a score like 18 out of 25 into a letter grade?
Divide the points you earned by the points possible and multiply by 100: 18 ÷ 25 × 100 = 72%. Then find 72% on the scale — it falls in the 70–72% band, which is a C−.
Is a 90% an A or an A−?
On this plus/minus scale, 90–92% is an A−, 93–96% is an A, and 97% and above is an A+. Schools that don't use plus and minus grades usually count everything from 90% to 100% as a plain A.
What is the lowest passing grade?
On most US scales, a D− (60%) is the lowest passing grade and anything below 60% is an F. Many programs, however, require a C or C− (around 70–73%) for a course to count toward a major or a prerequisite.
Should I round my percentage before looking up the grade?
That depends on your teacher. Some round to the nearest whole percent (so 89.5% becomes 90% and an A−), while others use the exact number (89.5% stays a B+). This calculator uses the exact percentage you enter.