A 50-question test
- Input
- 42 correct answers out of 50 questions, each worth 1 mark.
- Working
- Score = 42 ÷ 50 × 100 = 0.84 × 100 = 84%. The 84% score falls in the 83–86% band.
- Result
- Score = 84% (B), with 8 questions wrong
Test Score Calculator
Turn correct answers or points earned into a percentage and letter grade the moment a test is marked — free, in your browser. Runs entirely in your browser — your numbers never leave this device.
Your score
84.0%
42 out of 50 points is a B (3.0 grade points).
- Percentage
- 84%
- Letter grade
- B
- Grade points
- 3.00
- Points missed
- 8
| Target score | Wrong answers you can afford | Correct answers needed |
|---|---|---|
| 90% | 5 | 45 |
| 80% | 10 | 40 |
| 70% | 15 | 35 |
| 60% | 20 | 30 |
The table looks ahead, not back: it shows how many questions you could miss on a fresh test of 50 questions and still hit each target. It assumes every question is worth the same number of points.
How it works
Score % = (correct answers ÷ total questions) × 100, or (points earned ÷ total points) × 100; wrong answers = total − correct
A test score percentage is simply the share of the test you got right. If every question is worth the same, divide your correct answers by the total number of questions and multiply by 100. If questions carry marks, divide the points you earned by the total points available instead — the formula is identical, only the units change. The calculator then maps the percentage to a letter grade on the standard bands (87–89% = B+, 83–86% = B, 80–82% = B−, and so on).
You can also work from the number you got wrong, which is often what you know while marking: subtract wrong answers from the total to get correct answers, then apply the same formula. Note that this assumes no penalty for wrong answers. Tests with negative marking, such as some entrance exams that deduct a fraction of a mark per error, need the penalty subtracted from your earned points first.
Weighted sections are the other common wrinkle: if a paper has sections worth different totals, score each section, add the earned points, and divide by the combined total rather than averaging the section percentages. Averaging percentages directly would give a short section the same influence as a long one, which misstates the score.
Worked examples
A short 20-question quiz
- Input
- 17 correct answers out of 20 questions.
- Working
- Score = 17 ÷ 20 × 100 = 0.85 × 100 = 85%. The 85% score falls in the 83–86% band.
- Result
- Score = 85% (B), with 3 questions wrong
Working from wrong answers
- Input
- 45-question test, 9 answers wrong.
- Working
- Correct answers = 45 − 9 = 36. Score = 36 ÷ 45 × 100 = 0.80 × 100 = 80%. The 80% score falls at the bottom of the 80–82% band.
- Result
- Score = 80% (B−), with 36 correct out of 45
Frequently asked questions
How many questions can I miss and still get an A?
Work backwards from 90%, the usual A− threshold. On a 50-question test you need at least 45 correct, so you can miss at most 5. On a 40-question test you need 36 correct, so at most 4 wrong. The general rule: maximum misses = total questions × 0.10, rounded down.
What if questions are worth different marks?
Use points instead of question counts: divide the marks you earned by the total marks available. A test with ten 1-mark questions and five 4-mark questions is out of 30 marks, not 15 questions. Entering question counts for an unequally weighted test is the most common reason a score calculation comes out wrong.
Does this handle negative marking?
Not automatically. If your exam deducts marks for wrong answers — for example 0.25 marks per error — subtract the total penalty from your earned marks first, then enter the adjusted figure as points earned. The percentage formula itself is unchanged once the penalty is accounted for.
Are my scores saved anywhere?
No. This calculator runs 100% in your browser and stores nothing — the answers and scores you enter are processed on your device only and are never uploaded or recorded. When you leave the page, nothing remains.
Why does my teacher's letter grade differ from the one shown?
Teachers may round percentages before assigning letters, apply a curve, or use slightly different band edges than the standard table here. A score of 86.7%, for instance, may be rounded to 87% and become a B+ in one class and stay a B in another. The percentage itself is exact; the letter depends on your teacher's stated policy.
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