Calculate test score percentages, letter grades, and printable teacher grading charts.
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Test grade percentage is calculated using the formula: Score (%) = ((Total Questions - Wrong Questions) / Total Questions) × 100. For example, missing 4 questions on a 40-question test yields (36 / 40) × 100 = 90% (Letter grade A-).
An Easy Grader is a reference chart used by teachers that lists every possible number of missed questions (from 0 to N) alongside the corresponding percentage and letter grade. It allows rapid batch grading of student exams without typing each score into a calculator.
To get an A (90%), the maximum allowed wrong questions is floor(Total Questions × 0.10). On a 50-question test, you can miss up to 5 questions (50 × 0.10 = 5).
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