How Many Questions Can I Miss?
Enter your test length and target grade — find out the maximum you can get wrong and still hit your goal.
Test Details
Guessing Adjustment
Miss Tolerance Table
See exactly how many questions you can miss for every grade tier on this 50-question test.
| Target Grade | % Needed | Min Correct | Max Misses |
|---|---|---|---|
| A+ | 97% | 49 / 50 | 1 |
| A | 93% | 47 / 50 | 3 |
| A- | 90% | 45 / 50 | 5 |
| B+ | 87% | 44 / 50 | 6 |
| B | 83% | 42 / 50 | 8 |
| B- | 80% | 40 / 50 | 10 |
| C+ | 77% | 39 / 50 | 11 |
| C | 73% | 37 / 50 | 13 |
| C- | 70% | 35 / 50 | 15 |
| D | 60% | 30 / 50 | 20 |
How to Calculate the Maximum Wrong Answers You Can Have
When you're walking into a test, the single most important number to know is your "safety margin" — exactly how many questions you can afford to guess on or get wrong while still achieving your desired grade. Our calculator does the math for you instantly. To calculate it yourself:
- Determine your target grade percentage (e.g., 80% for a B).
- Convert it to a decimal (0.80) and multiply by the total number of questions on the test.
- Round that number up to the nearest whole number. That is your minimum correct answers needed.
- Subtract your minimum correct answers from the total questions to get your maximum allowed misses.
How Many Questions Can I Miss on a 20-Question Test?
On a 20-question quiz, every single question is worth a massive 5% of your total grade. This leaves very little room for error.
- To get an A (90%): You can miss exactly 2 questions. (18/20 = 90%)
- To get a B (80%): You can miss up to 4 questions. (16/20 = 80%)
- To get a C (70%): You can miss up to 6 questions. (14/20 = 70%)
- To pass (60%): You can miss up to 8 questions. (12/20 = 60%)
How Many Can I Miss on a 50-Question Test?
A 50-question exam is standard for midterms. Each question is worth exactly 2% of your overall grade.
- To get an A (90%): You can miss 5 questions. (45/50 = 90%)
- To get a B (80%): You can miss 10 questions. (40/50 = 80%)
- To get a C (70%): You can miss 15 questions. (35/50 = 70%)
- To pass (60%): You can miss 20 questions. (30/50 = 60%)
How Many Can I Miss on a 100-Question Test?
For final exams, 100-question formats are common. The math here is simple: every question is exactly 1% of your grade. To get a 90%, you can miss 10 questions. To get an 85%, you can miss 15 questions. Because the test is so long, you have a much larger safety buffer for random mistakes.
What Happens If You Guess on Missed Questions?
If your test is multiple choice, never leave a question blank unless there is a guessing penalty (like on the SAT). If you have a 4-option multiple choice test and you don't know the answer to 12 questions, guessing will statistically yield 3 correct answers (25% of 12). Use our "Guess Impact" feature in the calculator above to see how random guessing statistically improves your margin of error.
Frequently Asked Questions
On a 50-question test, you can miss a maximum of 10 questions and still score 80%. You need to answer at least 40 out of 50 correctly. Missing 11 or more would drop your score below 80% (78%).
Multiply the total number of questions by your target percentage (as a decimal), then round up to get the minimum correct answers needed. Subtract that from the total. For example: 30 questions × 0.70 = 21 correct needed (round up to 21). Max wrong = 30 − 21 = 9 questions.
Yes, 100% free with no account or signup required. All calculations run instantly in your browser — nothing is saved or sent to any server. The full miss tolerance table updates in real time as you type.
A typical passing grade is 60%. On a 20-question test, you need at least 12 correct answers (60%), meaning you can miss a maximum of 8 questions. To get a B (80%), you can miss only 4 questions. To get an A (90%), you can miss at most 2 questions.
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