Letter Grade Calculator Formula

Understand the math behind the letter grade calculator. Each variable explained with a worked example.

Use the Letter Grade Calculator

Formulas Used

Grade Points (4.0 Scale)

grade_points = percentage >= 93 ? 4.0 : (percentage >= 90 ? 3.7 : (percentage >= 87 ? 3.3 : (percentage >= 83 ? 3.0 : (percentage >= 80 ? 2.7 : (percentage >= 77 ? 2.3 : (percentage >= 73 ? 2.0 : (percentage >= 70 ? 1.7 : (percentage >= 67 ? 1.3 : (percentage >= 60 ? 1.0 : 0)))))))))

Pass or Fail

pass_fail = percentage >= 60 ? 1 : 0

1 = Pass, 0 = Fail

Percentage

percentage_out = percentage

Variables

VariableDescriptionDefault
percentageGrade Percentage(%)87

How It Works

How to Convert Percentage to Letter Grade

The standard grading scale maps percentage ranges to letter grades.

Standard Scale

| Percentage | Letter | Points | |-----------|--------|--------| | 93-100 | A | 4.0 | | 90-92 | A- | 3.7 | | 87-89 | B+ | 3.3 | | 83-86 | B | 3.0 | | 80-82 | B- | 2.7 | | 77-79 | C+ | 2.3 | | 73-76 | C | 2.0 | | 70-72 | C- | 1.7 | | 67-69 | D+ | 1.3 | | 60-66 | D | 1.0 | | Below 60 | F | 0.0 |

Worked Example

A student scores 87% in a course.

percentage = 87
  1. 01Score: 87%
  2. 0287% falls in the 87-89 range
  3. 03Letter grade: B+
  4. 04Grade points: 3.3

Ready to run the numbers?

Open Letter Grade Calculator