Quiz Grade Calculator
Enter the number of correct answers and total questions. Get instant percentage, letter grade, and points wrong.
18 out of 25 points — 7 wrong
How quiz grades are calculated
Standard percentage grade = (correct answers ÷ total questions) × 100. A student who answers 18 of 25 correctly scores 18/25 = 72%.
For weighted quizzes (when some questions are worth more), use the weighted total: sum of (points earned per item) ÷ sum of (max points per item) × 100.
Standard letter grade conversion (US)
| Percentage | Letter | GPA (typical) |
|---|---|---|
| 97-100 | A+ | 4.0 |
| 93-96 | A | 4.0 |
| 90-92 | A- | 3.7 |
| 87-89 | B+ | 3.3 |
| 83-86 | B | 3.0 |
| 80-82 | B- | 2.7 |
| 77-79 | C+ | 2.3 |
| 73-76 | C | 2.0 |
| 70-72 | C- | 1.7 |
| 67-69 | D+ | 1.3 |
| 63-66 | D | 1.0 |
| 60-62 | D- | 0.7 |
| Below 60 | F | 0.0 |
Bonus points and extra credit
When bonus questions count toward the numerator but not denominator, a student can score above 100%. Example: a 20-question quiz with 2 bonus items. A student getting all 22 right scores 22/20 = 110%.
When extra credit replaces a missed answer, simply add the bonus points to the earned column without changing the total.
Quick mental math
- · 1 wrong out of 20 = 95% (each item = 5%)
- · 1 wrong out of 25 = 96% (each item = 4%)
- · 1 wrong out of 50 = 98% (each item = 2%)
- · 1 wrong out of 100 = 99% (each item = 1%)
For any quiz, errors ÷ total = error rate. 100% − error rate = score. 3 wrong out of 30 = 10% error = 90% score.
Tips for teachers
- · Announce the scoring scheme upfront. Students need to budget time per question.
- · Use weighted scoring when some items genuinely require more thinking. A 5-point essay shouldn't equal a 1-point MCQ.
- · Cap perfectionism. Bonus questions provide a release valve for students chasing 100% without inflating grades for the class as a whole.
- · Track item difficulty. When 60% of students miss the same item, the item — not the students — is usually the problem.