Letter Grade Calculator
Convert any numerical score or percentage to a letter grade instantly. Supports the standard A–F scale and the plus/minus (A+ to F) scale used by most schools and universities.
Standard Scale
Plus/Minus Scale
Why Use This Letter Grade Calculator?
- ✓Instant conversion from percentage to letter grade with no signup
- ✓Two grading scales — standard A–F and detailed plus/minus
- ✓Matching GPA values so you can plan your grade point average
- ✓100% free and works on any device
What Is a Letter Grade Calculator?
A letter grade calculator converts a numerical score or percentage into the corresponding letter grade (A, B, C, D, or F) based on a chosen grading scale. Instead of memorizing cutoffs or doing the math by hand, you enter a score like 88% and instantly see that it maps to a B+ on a plus/minus scale. Teachers use it to grade assignments quickly, students use it to check where their percentage lands, and parents use it to understand report cards. Our free tool supports both the standard A–F scale and the more granular A+ to F scale so it matches almost any school or university system.
Standard Grading Scale (Percentage to Letter Grade)
Most schools in the United States follow a 10-point grading scale. Here is the standard conversion chart that this calculator uses by default:
| Letter Grade | Percentage Range | GPA (4.0 Scale) | Meaning |
|---|---|---|---|
| A | 90–100% | 4.0 | Excellent |
| B | 80–89% | 3.0 | Above average |
| C | 70–79% | 2.0 | Average |
| D | 60–69% | 1.0 | Below average / passing |
| F | Below 60% | 0.0 | Failing |
Plus/Minus (A+ to F) Grading Scale
Many high schools, colleges, and universities use a more detailed scale that adds plus and minus modifiers. This gives a finer picture of performance and affects weighted GPA. The most common plus/minus breakdown is:
A range
A+ = 97–100% (4.0), A = 93–96% (4.0), A− = 90–92% (3.7)
B range
B+ = 87–89% (3.3), B = 83–86% (3.0), B− = 80–82% (2.7)
C range
C+ = 77–79% (2.3), C = 73–76% (2.0), C− = 70–72% (1.7)
D & F range
D+ = 67–69% (1.3), D = 63–66% (1.0), D− = 60–62% (0.7), F = below 60% (0.0)
How to Calculate Your Letter Grade (Step by Step)
- 1.Find your percentage. Divide the points you earned by the total possible points, then multiply by 100. Example: 43 out of 50 = (43 ÷ 50) × 100 = 86%.
- 2.Choose your grading scale. Select the standard A–F scale or the plus/minus (A+ to F) scale that your school uses.
- 3.Match the percentage to a range. An 86% falls in the 83–86% band, which is a B on the plus/minus scale.
- 4.Read your GPA value. A B is worth 3.0 grade points, which you can use in our GPA Calculator.
Real Examples: Score to Letter Grade
Example 1: 47 out of 50 on a quiz
Percentage = (47 ÷ 50) × 100 = 94%
Result: A (or A on the plus/minus scale)
Example 2: 68 out of 100 on a final exam
Percentage = 68%
Result: D+ on the plus/minus scale, D on the standard scale
Example 3: 215 out of 250 total course points
Percentage = (215 ÷ 250) × 100 = 86%
Result: B
Why Grading Scales Differ Between Schools
There is no single national grading standard, so cutoffs vary. Some institutions use a 7-point scale where an A starts at 93%, while others give an A at 90%. Honors and Advanced Placement (AP) courses often use weighted scales that add 0.5 or 1.0 GPA points, which is why a student can finish with a GPA above 4.0. Always confirm the exact scale on your syllabus or student handbook before relying on a conversion, and use this calculator with the scale that matches your course.
Common Questions About Letter Grades
What percentage is an A?
On the standard 10-point scale, an A is 90% or higher. On a plus/minus scale, a straight A is usually 93–96%, an A− is 90–92%, and an A+ is 97–100%.
Is a D a passing grade?
In most schools a D (60–69%) is technically a passing grade for the course, but many colleges and programs require a C or higher for the credit to count toward a major or transfer.
What is the lowest passing grade?
The lowest passing letter grade is typically a D− at 60%. Anything below 60% is an F, which does not earn credit.
Do colleges use the same grading scale as high schools?
Not always. Many colleges use plus/minus grading and may set an A at 93% rather than 90%. Some professors set their own cutoffs, so check each syllabus.
How do I convert my letter grade to a GPA?
Each letter maps to grade points: A = 4.0, B = 3.0, C = 2.0, D = 1.0, F = 0.0. Average those values across your courses to get your GPA, or use our GPA Calculator.