A quiz grade calculator turns a raw assessment score into a percentage and a letter grade. Use count mode when every question is worth one point and you know the number wrong or correct; use points mode when the quiz has partial credit, mixed point values, or bonus points.
Results update as you type.
Choose count mode for number wrong/correct, or points mode for partial-credit scores. Hidden fields are skipped automatically.
Combines the fast teacher workflow from easy graders (total questions plus wrong answers) with a points mode for partial-credit assessments, then shows both percentage and a syllabus-check letter grade.
Divide correct answers by total questions, then multiply by 100 to get the percentage grade. In points mode, substitute points earned and points possible.
Percentage Grade = (Correct Answers / Total Questions) × 100
Used in count mode when the user enters number correct, or as the canonical conversion in points mode after substituting earned points for C and possible points for Q.
Subtract wrong answers from total questions to find correct answers, then divide by total questions and multiply by 100.
Percentage Grade = ((Total Questions - Wrong Answers) / Total Questions) × 100
Used in count mode when the user enters number wrong. Equivalent to the correct-answer form because C + W = Q.
Compare the percentage to each ten-point threshold from highest to lowest, then assign the first matching letter grade.
Letter Grade = A if Percentage ≥ 90, B if ≥ 80, C if ≥ 70, D if ≥ 60, else F
Standard US ten-point straight scale with no plus/minus tiers.
Check the percentage against each plus-minus cutoff from highest to lowest, then assign the first matching letter grade with its modifier.
Letter Grade = A+ if Percentage ≥ 97, A if ≥ 93, A- if ≥ 90, B+ if ≥ 87, B if ≥ 83, B- if ≥ 80, C+ if ≥ 77, C if ≥ 73, C- if ≥ 70, D+ if ≥ 67, D if ≥ 63, D- if ≥ 60, else F
Three-tier-per-letter US convention with cutoffs at the standard 90/80/70/60 thresholds, splitting each ten-point band into -, base, and + sub-bands.
The calculator first converts the input into earned points over possible points. In count mode, correct answers equal total questions minus wrong answers (or the correct-answer count you enter directly). In points mode, points earned and points possible are used as entered so partial credit and extra credit are preserved. The result is earned ÷ possible × 100, then a letter grade is assigned from the selected straight-letter or plus/minus scale.
Maya grades a 40-question biology quiz and marks 7 answers wrong. Count mode subtracts 7 from 40, so the score is 33 correct out of 40. Dividing 33 by 40 and multiplying by 100 gives 82.5%. On the plus/minus scale, 82.5% maps to B-; on a straight A/B/C/D/F scale it maps to B.
Carlos earns 43 points on a lab report worth 50 points. Points mode divides 43 by 50 and multiplies by 100: 43 ÷ 50 × 100 = 86%. That is a B on both the straight-letter scale and the common plus/minus scale.
Use this calculator for a single quiz, test, exam, homework set, or assignment score. Teachers can grade a stack of equal-point quizzes by entering total questions and wrong answers, while students can check a points-earned score such as 43 out of 50. For a full course average with syllabus weights, use a weighted grade calculator instead.
Points earned and points possible appear on most returned quizzes. Teachers often write them as a fraction, like 17/20. The top number is points earned and the bottom is points possible. Enter both numbers exactly as they appear on your paper.
Schools do not all use the same letter grade cutoffs. Some use a standard scale that assigns grades in 10-point bands. Others use a plus-minus scale that gives finer distinctions within each band. The quiz grade calculator supports both options so your result matches what your school uses.
A single quiz grade tells you how you did that day. Running the calculator after each quiz in a unit shows you a pattern over time. A rising percentage grade means your study habits are working. A flat or falling trend signals that you may need to change your approach before the next test.