EZ Grader
Calculate test grades from questions missed. Get percentage scores, letter grades and a grading chart for your next stack of quizzes.
EZ Grader Calculator
Calculate test percentages and letter grades instantly. Create a grading chart for any test length.
Test Grading Chart
Find the number missed to see the score and letter grade.
| Incorrect | Correct | Score | Letter Grade |
|---|
Scores assume all questions have equal value. Letter grades use the selected scale. Your school may use different grading cutoffs or rounding rules.
On this page: 6 Sections
1. How to Use the EZ Grader Calculator
Start by checking each student’s test paper and counting the incorrect answers. Once you have the results, use the
calculator to quickly determine percentages and letter grades.
1. Enter the Total Number of Questions
Type the number of questions in the Questions on the Test field. The calculator will immediately determine the value of each question and generate a grading chart for your test.
2.Enter Each Student’s Incorrect Answers
Enter the number of missed questions under Wrong. You can also add a name in the optional Student field to identify each paper. Click + Add Student to enter additional students and calculate their grades.
3.Review and Record the Results
The Score section displays each student’s percentage and corresponding letter grade. Open Options to adjust the grading scale, include half-point deductions in the chart, or round percentages to whole numbers according to your school’s grading policy.
Click Try a Sample to load an example quiz with 25 questions and four students: Ava, Ben, Chloe, and Diego. You can use these sample results to understand how the calculator works.
Understanding Your EZ Grader Results
Your results depend on the information you enter. You can calculate a grade for a single test, compare several students’ scores, or review the overall performance of the class.
Quiz Results & Grading Overview
Understand how incorrect answers affect scores, how student grades are displayed, and how class performance is summarized.
HOW THE SCORE IS CALCULATED
For a 25-question quiz with equal-value questions and no penalty beyond lost points, each correct answer is worth 4 percentage points.
Understanding the Results
A quick guide to the information shown in the quiz report.
| Result | Example | What It Means |
|---|---|---|
| Each wrong answer costs | 4 points | The score decreases by 4 percentage points for every incorrect answer. One wrong gives 96%; three wrong give 88%. |
| Student's score | 80% B− | Shows one student's percentage, letter grade, and number of correct answers. |
| Class average | 83% B | The average of the individual scores for all students included in the report. |
| Highest · Lowest | 96% · 64% | The highest and lowest student scores in the class. |
| Grading chart | 26 rows | Lists the score and letter grade for every possible number of wrong answers, from 0 to 25. |
Sample Class Results
Example results for four students taking the same 25-question quiz.
Class Summary
| Statistic | Result | Explanation |
|---|---|---|
| Class average | 83% | (92 + 80 + 96 + 64) ÷ 4 = 83% |
| Highest score | 96% | Chloe scored highest. |
| Lowest score | 64% | Diego scored lowest. |
| Score range | 32 points | 96 − 64 = 32 percentage points. |
Leave a student’s Wrong field blank if you have not entered their result yet. Enter 0 if the student answered every
question correctly. Blank entries should not be treated as zero scores when calculating class averages.
Use the class average and score range as a starting point for reviewing student performance. If several students
missed the same questions, check the answer key, question wording, and topics covered in class. A single low score
does not automatically mean the test was too difficult or that a student has not understood the material. Consider the
individual student’s needs and the wider class results before deciding what to review or reteach.
2. EZ Grader: Calculate Test Scores Using Wrong Answers
Have a pile of quizzes to grade? The EZ Grader makes the process faster and easier. Enter the total number of
questions and the number of incorrect answers for each student, and the calculator instantly displays percentage
scores, letter grades, and the class average. You can also use the grading chart to find the possible score for each
number of mistakes, making it simple to grade multiple papers without calculating every result manually.
This easy grader works best for tests where every question has the same value, such as spelling tests, multiple-choice
quizzes, and classroom assessments with equal points per question. Students can also use it to estimate their grades
before results are officially recorded. If your assessment uses questions with different point values, calculate the grade
by dividing points earned by total points possible. For courses with weighted homework, exams, and other grading
categories, try the Grade Calculator instead.
3. EZ Grader Grading Scale: Convert Percentages to Letter Grades
To choose how your test scores convert into letter grades, open Options → Grading Scale. The plus/minus scale assigns
an A at 93%, an A− at 90%, a B+ at 87%, and a B at 83%. The standard 10-point scale uses a simpler system: A starts at 90%
, B at 80%, C at 70%, and D at 60%, without plus or minus grades. Switching between these options changes the letter grade displayed, but your percentage score stays the same.
Test Score Grading Comparison
See how the same test percentage can receive different letter grades depending on whether a plus/minus scale or a 10-point grading scale is used.
Grade Comparison Table
Compare each test score with its assigned letter grade under both grading systems.
| Test Score | Plus/Minus Scale | 10-Point Scale |
|---|---|---|
| 92% | A− | A |
| 88% | B+ | B |
| 80% | B− | B |
| 77% | C+ | C |
| 64% | D | D |
What Is the Difference?
Each grading system uses its own percentage cutoffs.
Plus/Minus Scale
Uses grades such as A−, B+, B−, and C+ to distinguish performance within a letter-grade range.
10-Point Scale
Typically assigns a letter grade to each 10-percentage-point band, though exact cutoffs can vary by school.
You can also use the grading chart to estimate letter grades for a points-based test when every question or point has
equal value. Enter the total possible points in Questions on the Test, then review the Grading Chart for N Questions.
Each row displays the number of correct answers, the percentage score, and the corresponding letter grade, helping you
identify the minimum score needed to earn each grade.
Keep in mind that the chart assumes equal-value questions. If individual questions have different point values, calculate
the percentage using total points earned divided by total points possible before assigning a letter grade.
4. How to Calculate a Test Grade From Incorrect Answers
Formula
Test Score (%) = (Total Questions − Incorrect Answers) ÷ Total Questions × 100
In this formula, Total Questions refers to the number of scored questions on the test, assuming every question has equal value. Incorrect Answers represents the number of questions answered incorrectly or left unanswered. If your test allows partial credit, a value such as 0.5 can represent half a question’s worth of lost credit.
Each incorrect answer reduces your score by percentage points. To calculate your grade, subtract the number of incorrect answers from the total questions, divide the result by the total, and multiply by 100.
Test Grade Calculation Example
Suppose Ben takes a quiz with 25 questions and answers 5 incorrectly.
How to Calculate Your Quiz Score
Learn how to calculate the value of each missed question, find your correct answers, and convert your result into a percentage.
You answered 20 out of 25 questions correctly.
Step-by-Step Calculation
Follow each step to understand where the final score comes from.
| Calculation Step | Numbers Used | Result |
|---|---|---|
| Points per question | 100 ÷ 25 | 4 points |
| Questions answered correctly | 25 − 5 | 20 questions |
| Percentage score | 20 ÷ 25 × 100 | 80% |
| Final result | 20 correct out of 25 | 80% |
The Formula Explained
Percentage Score Formula
Substitute the quiz results: (20 ÷ 25) × 100 = 80%
Remember
Ben earns a score of 80% on the quiz. His corresponding letter grade depends on the grading scale selected in the EZ Grader calculator.
5. EZ Grader chart: test scores and printable grading tables
Read the chart across: find the number wrong, and the same row gives the number right, the percent and the letter.
Grading chart for N questions sits beneath the result, with one row for every possible number wrong. Here are the
first rows for a 25-question test:
Quiz Score & Grade Chart
Check how the number of wrong answers affects your quiz score and letter grade.
Grading Scale
Each correct answer is worth 4 percentage points.
| Wrong | Right | Score | Letter |
|---|---|---|---|
| 0 | 25 | 100% | A+ |
| 1 | 24 | 96% | A |
| 2 | 23 | 92% | A− |
| 3 | 22 | 88% | B+ |
| 4 | 21 | 84% | B |
| 5 | 20 | 80% | B− |
| 6 | 19 | 76% | C |
How many questions can a student miss?
Use this quick grading table when you need the most whole questions a student can miss and still reach a letter threshold.
Each question must have equal value.
Quiz Grade Cutoff Chart
Find the maximum number of questions you can miss and still earn each listed grade, based on the total number of quiz questions.
Maximum Questions Missed
Each value shows the most questions you may answer incorrectly while meeting the indicated grade threshold.
| Questions | A 93%+ | B 83%+ | C 73%+ | D− 60%+ |
|---|---|---|---|---|
| 10 | 0 | 1 | 2 | 4 |
| 12 | 0 | 2 | 3 | 4 |
| 15 | 1 | 2 | 4 | 6 |
| 20 | 1 | 3 | 5 | 8 |
| 25 | 1 | 4 | 6 | 10 |
| 30 | 2 | 5 | 8 | 12 |
| 40 | 2 | 6 | 10 | 16 |
| 50 | 3 | 8 | 13 | 20 |
| 100 | 7 | 17 | 27 | 40 |
How to read this chart
- Choose the row matching the total quiz questions.
- Find the grade threshold you want to achieve.
- The number in that column is the maximum allowed wrong answers.
How percentages work
For equally weighted questions, calculate the percentage by dividing correct answers by total questions and multiplying by 100.
How to print or save your grading chart
Enter the question count and open Grading chart for N questions. To print, choose Options → My saves → Print / Save as PDF and check the print preview. Keep the chart beside your papers and use the Wrong column to find each score.
Keep one chart per test length
A 20-question chart does not fit a 25-question quiz. Change the question count before using the chart on a different test.
6. EZ Grader scores: partial credit, rounding and grade curves
Partial credit, rounding rules, and school grading policies can affect the final percentage or letter grade. For accurate records, keep the original test score separate from any additional adjustments made by your teacher or gradebook.
Partial Credit and Half-Point Deductions
Suppose Ben loses only half the credit for one of his five missed questions. Enter 4.5 in the Wrong field to represent four fully incorrect answers and one half-point deduction. His adjusted test score becomes:On the plus/minus grading scale, this score corresponds to a B−. To include half-question increments in the grading chart, open Options and enable Half Points in the Chart (0.5, 1, 1.5, …).
Grading Tests With Different Point
ValuesWhen questions carry different point values, counting incorrect answers alone will not give you an accurate grade. For example, a test might include multiple-choice questions worth two points each and an essay worth ten points. In this situation, calculate the percentage using the total points earned divided by the total points possible.If a student earns 31 out of 40 possible points, the score is:On the plus/minus scale described above, 77.5% corresponds to a C+. The result depends on points earned, not simply the number of questions missed.
Rounding Scores Near Letter-Grade
CutoffsRounding can change a letter grade when a score falls close to a grading threshold. For example, missing two questions on a 15-question quiz produces a score of approximately 86.67%. Without whole-number rounding, the calculator displays 86.7%, which corresponds to a B on the plus/minus scale. If you enable Round Scores to Whole Numbers, the result becomes 87%, corresponding to a B+.Keep in mind that displaying fewer decimal places is not the same as rounding the score before assigning a letter grade. Follow your school’s rules for rounding individual tests, since the policy used for final report cards may differ.
Some teachers adjust test scores using a grading curve. One approach is to add the same number of percentage points to every student’s original score. For example, a four-percentage-point adjustment would raise Chloe’s 96% to 100%, Ben’s 80% to 84%, and Diego’s 64% to 68%. The adjusted class average would be 87%, or a B+ on the plus/minus scale.You can explore possible adjustments with the Grade Curve Calculator. Before applying a curve, review the assessment for ambiguous questions, errors, or other issues and follow your school’s grading policy.Some gradebooks also use a minimum score policy, sometimes called a score floor, which prevents a recorded grade from falling below a specified threshold. Keep the original test percentage separate and apply a minimum score only when your school’s rules require it. The EZ Grader does not automatically apply this adjustment.
Not every school evaluates student performance using percentages and letter grades. In standards-based grading, teachers assess how well students demonstrate specific skills or meet learning objectives, often using a rubric with proficiency levels.For example, Kalamazoo Public Schools uses a competency-based grading approach in which a level of 3 represents the grade-level target. These proficiency ratings are not directly interchangeable with traditional percentage grades.If your school uses standards-based grading, consult the district’s rubric to interpret student results rather than converting a test percentage directly into a proficiency level.
Frequently Asked Questions
What is an EZ Grader calculator?
An EZ Grader is a tool that helps teachers and students calculate test percentages and letter grades using the number of questions on a test and the number of incorrect answers. It also provides a grading chart showing possible scores for different numbers of mistakes.
How do you calculate a test grade using wrong answers?
Subtract the number of incorrect answers from the total number of questions, divide the result by the total questions, and multiply by 100.Formula: Test Score (%) = (Total Questions − Incorrect Answers) ÷ Total Questions × 100.For example, if you answer 20 out of 25 questions correctly, your test score is 80%.
How many questions can I enter into EZ Grader?
The number of questions supported depends on the calculator you use. This EZ Grader version accepts test lengths from 1 to 200 questions, allowing you to calculate grades for short quizzes, classroom tests, and longer assessments.
Can EZ Grader calculate half-point deductions?
Yes. Enable the half-point option to enter deductions such as 0.5, 1.5, or 2.5. The calculator then adjusts the percentage based on the partial credit lost. Make sure your test allows partial credit before using this feature.
How do I calculate a letter grade from a percentage?
Select the grading scale that matches your school’s policy. The plus/minus scale distinguishes grades such as B+, B, and B−, while the standard 10-point scale uses broader categories. Your letter grade may differ if your school uses different percentage cutoffs.