Grading Calculator – Free Online EZ Grader for Tests, Quizzes & Exams
This free online grader converts wrong answers into a percentage score and letter grade in real time. Enter total questions and the number of wrong answers — the easy grader online instantly shows the percentage, fraction, grade, and pass/fail result. Below the calculator, generate a full EZ grader chart for any test length, customise grade thresholds, and access a dedicated grader for teachers with one-tap wrong-answer controls. Works for quizzes, tests, exams, and any scored assignment.
Grading Calculator – Convert Wrong Answers to a Grade
Online EZ Grader
Enter total questions and wrong answers. Score updates instantly.
| # Wrong | # Correct | Score % | Grade |
|---|
The calculator works in two directions: enter wrong answers and the correct answers auto-fill, or enter correct answers and the wrong answers sync automatically. The +1 / −1 buttons next to the wrong answers field let teachers flip through papers quickly without retyping totals.
Teacher Quick Grader – Grade Papers One at a Time
This dedicated grader for teachers is optimised for fast classroom marking. Set the total questions once, then tap + for each wrong answer found while marking. The large score display updates with every tap — no typing needed between papers. Tap reset to start the next student.
Custom Letter Grade Scale
Different schools, teachers, and countries use different grade cutoffs. Use this section to set the minimum percentage for each letter grade. The main calculator and the EZ grader chart both update instantly to reflect your custom thresholds.
Grade Threshold Settings
Set the minimum percentage required for each letter grade.
Any score below the D minimum is graded F. The chart and result update immediately as you type.
Grading Estimate – What-If Scenarios
Use this grading estimate section to understand the boundaries of any test score. The values below update automatically as you adjust the main calculator.
On shorter tests, each wrong answer drops the score by a larger percentage. On a 10-question quiz, one wrong answer costs 10 percentage points. On a 100-question exam, one wrong answer costs only 1 percentage point. This is why the total number of questions matters as much as the number of mistakes.
How the Grading Calculator Works
- Find the number of correct answers
Subtract wrong answers from the total. If a student got 3 wrong on a 20-question quiz: Correct = 20 − 3 = 17.
- Calculate the percentage
Divide correct answers by total questions, then multiply by 100. Example: (17 ÷ 20) × 100 = 85.0%.
- Convert the percentage to a letter grade
Compare the percentage to the grade thresholds. At the default scale: 85% is a B (≥ 80% but < 90%). You can adjust the thresholds in the Custom Grade Scale section.
- Determine pass or fail
If the percentage meets or exceeds the D threshold (default 60%), the result is a pass. Below that threshold, the result is a fail. Many schools use 70% (C) as the pass mark — adjust the D threshold if needed.
Why Smaller Tests Change Percentages More Sharply
Each wrong answer on a 10-question quiz costs 10%. The same one missed question on a 100-question exam costs only 1%. This means grades on short quizzes are much more sensitive to individual mistakes. A student who would earn a 90% on a 100-question test might earn an 80% on the same knowledge tested in a 10-question format just by getting one extra question wrong.
Worked Example
A student takes a 25-question test and gets 4 wrong.
Percentage = (21 ÷ 25) × 100 = 84.0%
Grade = B (84% ≥ 80%, < 90%)
Test, Quiz & Exam Grading Examples
The table below shows common test scenarios with their scores, percentages, and letter grades at the default A/B/C/D/F scale.
EZ Grader Chart Reference – 20 Questions
The table below is a static reference EZ grader chart for a 20-question test. Use the dynamic chart in the calculator for any total.
| # Wrong | # Correct | Score | Grade |
|---|---|---|---|
| 0 | 20 | 100% | A |
| 1 | 19 | 95% | A |
| 2 | 18 | 90% | A |
| 3 | 17 | 85% | B |
| 4 | 16 | 80% | B |
| 5 | 15 | 75% | C |
| 6 | 14 | 70% | C |
| 7 | 13 | 65% | D |
| 8 | 12 | 60% | D |
| 9 | 11 | 55% | F |
| 10+ | 10 or fewer | 50% or below | F |
What Is an EZ Grader? Definition & Purpose
An EZ grader (also written as easy grader or EZ grader chart) is a grading tool that maps the number of wrong answers directly to a percentage score and letter grade, without requiring any calculation. The original physical EZ grader was a sliding card that teachers kept in their desk drawers. This online version replaces that card with an interactive, real-time calculator.
Why Teachers Use an Easy Grader
- Speed: Grading a stack of 30 papers by hand, calculating (correct ÷ total × 100) for every one, is slow and prone to arithmetic errors. An easy grader online converts every possible score in one glance.
- Accuracy: No rounding errors, no mental math mistakes. The calculator applies the same formula consistently to every score.
- Flexibility: Unlike a physical card, this easier grader works for any total — not just the common totals printed on the original sliding chart.
- Portability: Works on any phone, tablet, or computer. No physical card to lose or replace.
Who Can Use This Test Grader
- Teachers: Grade quizzes, tests, and exams quickly using the teacher mode with +/− buttons.
- Students: Check your own test score before it is officially returned. Estimate whether your score passes.
- Tutors and instructors: Grade practice tests and provide instant feedback during sessions.
- Homeschool parents: Grade worksheets and assessments without a separate grading tool.
- Test-prep coaches: Show students exactly how many questions they can afford to miss on a target score.
EZ Grader vs. Other Grade Calculators
There are several different grade-related calculators, each solving a different problem. Here is a quick guide to which tool to use.
EZ Grader / Test Grader (this page)
Converts wrong answers to a percentage and letter grade for a single test, quiz, or exam. Best for grading one assessment quickly.
GPA Calculator
Calculates Grade Point Average across multiple courses, semesters, or your full academic career. Uses credits and letter grades, not individual test scores.
Common Grading Mistakes to Avoid
- Entering correct answers as the "wrong" count (or vice versa). The most common input error. Double-check which field is labelled wrong answers and which is correct. This calculator syncs both fields, so you can enter either one.
- Forgetting bonus questions. If a test has bonus questions, those extra correct answers increase the numerator but the denominator stays fixed. This can push a score above 100%. The calculator handles values above 100% — just enter the total scored-question count and the actual wrong answers.
- Assuming all schools use the same letter-grade scale. A 79% is a C+ at one school and a B at another. Always confirm your institution's grading policy before applying any generic chart. Use the custom thresholds section to match your school.
- Confusing a test grader with a final course-grade calculator. A test grader tells you the score on one assessment. It cannot tell you your final course grade, which depends on assignment weights, attendance policies, and other factors. Use the weighted grade or final grade calculator for course-level questions.
- Rounding the percentage too early. If a test score is 89.5% and your A threshold is 90%, rounding to 90% before grading gives a different result than applying the 89.5% directly to the threshold. Use the 2-decimal rounding option when precision matters.
- Using the wrong total for partial-credit questions. This calculator assumes each question is worth the same number of points. If some questions are worth 2 points and others 1 point, the total should be entered as total points available and wrong as total points lost — not as question counts.