Test Grade Calculator

Related Calculators

Table of contents

• How to use
• Common mistakes
• Definitions
• Methodology
• Limitations & assumptions
• Sources

Questions correct: The number of questions you got right.

Questions incorrect: The number of questions you got wrong.

Total questions: The full number of questions on the test.

Percent grade: Your score written as a percent out of 100.

Letter grade: The letter assigned to your percent based on the selected grade scale.

Passing grade (%): The lowest percent that counts as passing in your class.

Correct answers required (total): The smallest whole-number total required to reach a target or pass.

Additional correct answers needed: The required total minus the questions already correct, never less than zero.

Questions you can miss: How many questions could be wrong while still meeting the chosen threshold.

Additional correct answers for next letter: How many more correct answers you need to move up to the next higher letter grade.

Mistake: Entering the number you missed in "Questions correct".
Fix: Put the number you got right in "Questions correct", or choose "Find my grade (from incorrect answers)" and enter the number you missed in "Questions incorrect".

Mistake: Typing points possible instead of the actual count in "Total questions".
Fix: Use the full number of questions in "Total questions" so "Percent grade" is based on the right test size.

Mistake: Using "Target grade (%)" as a letter like A or B.
Fix: Enter a number such as 90 in "Target grade (%)" and let "Correct answers required (total)" show the minimum correct answers.

Mistake: Forgetting that your class does not use the standard letter cutoffs.
Fix: Open Advanced options, change "Letter scale", and if needed enter custom "A starts at (%)", "B starts at (%)", "C starts at (%)", and "D starts at (%)" values before reading "Letter grade".

Mistake: Entering a "Passing grade (%)" over 100 or below 0.
Fix: Keep "Passing grade (%)" between 0 and 100 so "Pass result" and "Correct answers required (total)" can be calculated correctly.

Mistake: Thinking "Additional correct answers for next letter" is a percent gap.
Fix: Read "Additional correct answers for next letter" as extra questions correct needed, not extra percent.

• This calculator treats every question as worth the same amount and uses simple percent grading.
• It assumes whole-question scoring, so "Correct answers required (total)" is rounded up to the next whole question.
• "Letter grade" depends on the selected scale; many schools and teachers use different cutoffs.
• If your class drops questions, gives partial credit, weights sections differently, or curves scores, real grades can differ.
• "Questions correct" should not be greater than "Total questions" when checking an actual score.
• If a target or passing threshold would require more correct answers than the test has, the calculator can show that the goal is not reachable on this test.

How the calculator works

The calculator uses your test score and the selected mode to answer one of three common questions: what your current grade is, how many right answers you need for a target, or whether your score is enough to pass.

Formulas

Percent grade = (Questions correct / Total questions) x 100

From incorrect answers: Percent grade = ((Total questions - Questions incorrect) / Total questions) x 100

Questions missed = Total questions - Questions correct

Correct answers required (total) = ceil((Threshold percent / 100) x Total questions)

Additional correct answers needed = max(0, Correct answers required (total) - Questions correct)

Questions you can miss = Total questions - Correct answers required (total)

Pass result = Passing if Percent grade >= Passing grade (%), otherwise Not passing yet

Additional correct answers for next letter = max(0, ceil((Next cutoff percent / 100) x Total questions) - Questions correct)

Letter grade method

For the standard US scale, the calculator uses A at 90, B at 80, C at 70, and D at 60. For the plus/minus option, it uses the built-in cutoffs listed in the calculator. If you choose custom cutoffs, it uses your own A, B, C, and D starting percentages. The cutoffs must stay in strict order: A greater than B, B greater than C, and C greater than D.

Worked example

If you got 18 right out of 20, your percent grade is 90% because 18 divided by 20 is 0.9, and 0.9 x 100 = 90.

If your target is 85% on a 20-question test, the calculator finds the minimum whole number of right answers with ceil((85 / 100) x 20). That is ceil(17), so "Correct answers required (total)" is 17 and "Questions you can miss" is 3.

If your class uses the standard scale and you have 27 right out of 30, your percent is 90%. If custom cutoffs set A at 92 and B at 84, your current letter is B, and the next letter cutoff needs ceil((92 / 100) x 30) = 28 correct, so "Additional correct answers for next letter" is 1.

Assumptions and limits

This method matches simple raw-score grading and does not include weighted sections, extra credit, question-level partial credit, or score curves. Because real classrooms can use different rules, the calculator is best for quick planning and checking, not for replacing a teacher's exact grading system.