How to Calculate a Test Grade
Last updated: October 13, 2026
A test grade is the share of the test you got right, written as a percentage. Enter your score below to see your test grade right away, then read on for the formula, how curves work and how one test affects your class grade.
Number correct
Test grade = questions correct ÷ total questions × 100
Example: 42 correct out of 50 questions. 42 ÷ 50 = 0.84, so the grade is 84%.
Points earned
If questions are worth different points, or you earned partial credit, use points instead: points earned ÷ points possible × 100. Scoring 87 points out of 100 is 87%.
Example: a test has thirty 2-point multiple-choice questions and two 10-point essays, so 80 points are possible. You miss 4 multiple-choice questions, so 26 correct answers earn 52 points. You score 8 and 9 on the essays for 17 more. That is 52 + 17 = 69 points, and 69 ÷ 80 = 0.8625, so your grade is 86.3%. Always confirm the total points possible before you divide.
Test grade by number of questions missed
It is often faster to count what you missed than what you got right. This table shows the grade for common test lengths.
| Questions missed | 20-question test | 25-question test | 50-question test | 100-question test |
|---|---|---|---|---|
| 0 | 100% | 100% | 100% | 100% |
| 1 | 95% | 96% | 98% | 99% |
| 2 | 90% | 92% | 96% | 98% |
| 3 | 85% | 88% | 94% | 97% |
| 4 | 80% | 84% | 92% | 96% |
| 5 | 75% | 80% | 90% | 95% |
| 6 | 70% | 76% | 88% | 94% |
| 8 | 60% | 68% | 84% | 92% |
| 10 | 50% | 60% | 80% | 90% |
To find how many questions you can miss and still earn an A (90%), multiply the total by 0.10 and round down. On a 50-question test you can miss 5 and still have 90%.
How a test changes your class grade
A test only moves your class grade by the amount it is worth. In a points-based class, add the test’s points to your totals.
Example: before the test you have 400 out of 450 points, which is 88.9%. You score 42 out of 50 on the test. Now you have 442 out of 500 points, which is 88.4%.
If your class uses weighted categories, the test changes the average of its category, and that average counts for the category’s weight. See how to calculate a weighted grade.
If the test is curved
Use the curved score your teacher enters, not the raw score. Different teachers curve differently, so ask if you are unsure. Three common methods:
- Flat curve. Everyone gets the same number of points added. A 5-point curve turns a 78 into an 83.
- Scaled to the top score. If the best score is 92, every score is multiplied by 100 ÷ 92. A 78 becomes about 84.8.
- Square root curve. The new score is the square root of the raw score times 10. A 64 becomes 80 and a 78 becomes about 88.3.
Exam grade versus quiz grade
The calculation is the same for a quiz, a midterm and a final exam. What changes is the weight. A quiz may be worth 1% of your class grade and a final exam 25%, so the same score moves your overall grade very differently. When the exam is the final, use what do I need on my final to work backwards from the grade you want.
See the effect before the test
Add the upcoming test as an assignment in Grade Calculator, try different scores, and watch your class grade update.
Frequently asked questions
How do I calculate my test grade from questions correct?
Divide the number you got right by the total number of questions, then multiply by 100. Getting 42 out of 50 right is 42 ÷ 50 × 100 = 84%.
How many questions can I miss and still get an A?
Multiply the total number of questions by 0.10 and round down. On a 20-question test you can miss 2 and keep a 90%, and on a 100-question test you can miss 10.
Does one test grade really change my class grade?
It changes it by the weight the test carries. A test worth 5% of the class can move your grade a point or two, while a final worth 25% can move it much more.
Should I use the raw score or the curved score?
Use whichever score your teacher enters in the gradebook. If the curve has not been applied yet, treat the raw score as the safe estimate.
Calculate it automatically
Paste your gradebook into Grade Calculator and the table fills in on its own. Change any score, or add an upcoming assignment, to see your class grade update.