Test Grade Calculator
Enter the total number of questions and the number you got wrong to get your test percentage, letter grade, and a full EZ grader chart. Free to use, with no login required.
Calculate Your Test Grade
Use this tool for equally weighted questions with no partial credit. Each question counts the same, so your grade comes straight from the number of wrong answers.
Formula: correct answers = total questions − wrong answers; percentage = correct ÷ total × 100. Letter grades use the unrounded percentage, and the displayed percentage is rounded to two decimal places. Your school’s own scale decides the official grade.
Whether you are a teacher working through a stack of marked tests or a student staring at a returned exam, the test grade calculator turns a wrong-answer count into a clear percentage and letter grade in seconds. No sign-up, no spreadsheet, no mental math.
Teachers usually grade by counting what was missed: 5 wrong on a 50-question test, 2 wrong on a 20-question quiz. Students usually see the number wrong circled on a returned paper and want to know what it means. This page handles both directions. Enter the total questions and the wrong answers, and you get the number correct, the percentage to two decimal places, an example letter grade, and a complete EZ grader chart for that test length.
How to Use the Test Grade Calculator
Getting your grade takes three quick steps:
- Enter the total questions. Type the number of questions on the test — for example, 50.
- Enter the wrong answers. Type how many were missed or marked incorrect — for example, 5. Leave it at 0 for a perfect paper.
- Press Calculate Grade. The tool shows your correct answers, percentage, and letter grade instantly, along with a full chart of every possible wrong-answer count for that test.
Changed your mind? The “Clear and Calculate Again” button resets the tool so you can grade the next paper.
The Test Grade Formula
Behind the button is simple arithmetic. First the tool finds your correct answers, then it converts them to a percentage:
So a test with 50 questions and 5 wrong gives 45 correct, and (45 ÷ 50) × 100 = 90%. The letter grade is assigned from the unrounded percentage using the example scale further down this page, and the displayed percentage is rounded to two decimal places.
Wondering how many wrong answers you can afford? See our guide: How Many Questions Can You Miss and Still Pass (or Still Get an A)?
Worked Examples
Three walkthroughs show the math in action, step by step.
Example 1: 5 wrong out of 50 → 90%, A−
Correct answers = 50 − 5 = 45. Percentage = (45 ÷ 50) × 100 = 90.00%. On the example scale, 90% to below 93% is an A−.
Example 2: 4 wrong out of 30 → 86.67%, B
Correct answers = 30 − 4 = 26. Percentage = (26 ÷ 30) × 100 = 86.666…%, displayed as 86.67%. That sits in the 83% to below 87% band, so the letter grade is a B.
Example 3: 2 wrong out of 40 → 95%, A
Correct answers = 40 − 2 = 38. Percentage = (38 ÷ 40) × 100 = 95.00%. That falls in the 93% to below 97% band, so the letter grade is an A.
| Total Questions | Wrong | Correct | Percentage | Letter Grade |
|---|---|---|---|---|
| 50 | 5 | 45 | 90.00% | A− |
| 30 | 4 | 26 | 86.67% | B |
| 40 | 2 | 38 | 95.00% | A |
How to Read the EZ Grader Chart
After you calculate, the tool builds a complete EZ grader chart for your test length: one row for every possible number of wrong answers, from 0 up to the total. Find your wrong count in the first column and read across to see the correct count, the exact percentage, and the letter grade — no math required.
Teachers use these charts to grade a whole class quickly. Once the chart for a 40-question test is on the desk, every paper in the stack can be converted at a glance, and the chart works just as well pinned next to a grade book.
Notice how the cost of a single wrong answer changes with test length. On a 10-question quiz, each wrong answer costs a full 10 percentage points — two wrong is already 80%. On a 50-question test, each wrong answer costs only 2 points, so two wrong is still 96%. Short quizzes feel punishing because there are fewer questions to absorb each mistake, which is exactly what the chart makes visible.
Example Letter-Grade Scale
The calculator uses the same example plus/minus scale as the rest of this site:
| Letter Grade | Percentage Range |
|---|---|
| A+ | 97%–100% |
| A | 93% to below 97% |
| A− | 90% to below 93% |
| B+ | 87% to below 90% |
| B | 83% to below 87% |
| B− | 80% to below 83% |
| C+ | 77% to below 80% |
| C | 73% to below 77% |
| C− | 70% to below 73% |
| D+ | 67% to below 70% |
| D | 63% to below 67% |
| D− | 60% to below 63% |
| F | 0% to below 60% |
There is no single grading scale used by every school. Treat these letters as examples and always check your teacher’s or school’s official scale for the grade that counts.
What If Questions Carry Different Point Values?
Counting wrong answers works when every question is worth the same. But if some questions are worth more — an essay worth 20 points next to multiple-choice worth 2 — count points instead of questions.
The method is identical: add up the points you earned, divide by the total possible points, and multiply by 100. Earning 86 of 100 possible points is 86%, whatever the question mix. If your test is points-based, our grading calculator handles earned and possible points the same way.
Frequently Asked Questions
How do I calculate my test grade?
Subtract your wrong answers from the total questions to get your correct answers, then divide by the total and multiply by 100. The calculator at the top of this page does it instantly and adds the letter grade plus a full chart.
What is a good test grade?
Most students aim for the B range (83–87%) or higher, and many courses require at least a C (73%) for the credit to count well — but “good” depends on your goals and your school’s thresholds. The number that matters most is the one your teacher uses.
How many wrong answers can I get and still pass?
If passing means 60%, multiply the total questions by 0.60 and round up — that is the minimum number you need correct. On a 50-question test you need 30 correct, so you can afford 20 wrong. On a 25-question test you need 15 correct, so you can afford 10 wrong.
Does this work for quizzes and exams too?
Yes. Any assessment where every question counts the same works — pop quizzes, chapter tests, midterms, and final exams. For mixed point values, use points instead of question counts as described above.
Is the letter grade exact for my school?
Not necessarily. Schools use different scales — some use whole letters only, and cutoffs vary. This calculator’s letters are examples from a common plus/minus scale; your teacher’s or school’s scale decides your official grade.
Keep this page bookmarked for the next stack of tests. For related tools, try the grading calculator for correct-answer entry, the teacher grader for full-class grading charts, quick lookups like what 16 out of 20 or 11 out of 15 work out to, and what a 9/10 grade means, and the complete grade calculators hub.
More Grade Tools
Your test percentage is one piece of the puzzle. Explore the other free calculators:
Weighted Grade Calculator → Average Grade Calculator → All Calculators →