Test Grade Calculator
Use this test grade calculator to turn questions wrong into a score, with a chart you can print.
- Free
- No sign-up
- We never receive your grades
Your test
Your school's scale may differ. Set your own scale.
Quick lookup
| Wrong | Right | Percent | Letter |
|---|---|---|---|
| 0 | 20 | 100% | A |
| 1 | 19 | 95% | A |
| 2 | 18 | 90% | A |
| 3 | 17 | 85% | B |
| 4 | 16 | 80% | B |
| 5 | 15 | 75% | C |
| 6 | 14 | 70% | C |
| 7 | 13 | 65% | D |
| 8 | 12 | 60% | D |
| 9 | 11 | 55% | F |
| 10 | 10 | 50% | F |
| 11 | 9 | 45% | F |
| 12 | 8 | 40% | F |
| 13 | 7 | 35% | F |
| 14 | 6 | 30% | F |
| 15 | 5 | 25% | F |
| 16 | 4 | 20% | F |
| 17 | 3 | 15% | F |
| 18 | 2 | 10% | F |
| 19 | 1 | 5% | F |
| 20 | 0 | 0% | F |
| Letter | At least | Most wrong |
|---|---|---|
| A | 90% | 2 |
| B | 80% | 4 |
| C | 70% | 6 |
| D | 60% | 8 |
Saved in this browser.
How to use this test grade calculator
Enter your test size and read the chart. Each row shows wrong, right, percent and letter.
- In Number of questions or points, enter a size from 1 to 200.
- Pick a Grading scale. The 10-point scale comes first, and any scale you save on the Grading Scale page shows up here too.
- Use Step for half or quarter points, and Show percent as for a whole number or one decimal.
- For one score, use Quick lookup. Choose Questions wrong or Questions right, then type the number.
The How many can a student miss? table gives the most wrong answers for each letter.
How to calculate a test grade
Divide the questions right by the total questions, then multiply by 100.
Test grade = questions right ÷ total questions × 100
Made-up example: 3 wrong on a 20-question test leaves 17 right. 17 ÷ 20 × 100 = 85%, a B on both built-in scales.
Made-up example: 7 wrong on a 30-question test leaves 23 right. 23 ÷ 30 × 100 = 76.67%. With Whole number picked, the tool shows 77%. The letter still uses the exact percent, so on the Plus/minus scale it stays a C, because C+ starts at 77. Check My teacher rounds .5 up and it becomes a C+.
Test grade chart: number wrong, percent and letter
On a 20-question test, each question is worth 5%. If you know this kind of chart as an easy grader, it works the same way: find the number wrong and read across.
| Wrong | Right | Percent | 10-point scale | Plus/minus scale |
|---|---|---|---|---|
| 0 | 20 | 100% | A | A+ |
| 1 | 19 | 95% | A | A |
| 2 | 18 | 90% | A | A- |
| 3 | 17 | 85% | B | B |
| 4 | 16 | 80% | B | B- |
| 5 | 15 | 75% | C | C |
| 6 | 14 | 70% | C | C- |
| 7 | 13 | 65% | D | D |
| 8 | 12 | 60% | D | D- |
| 9 | 11 | 55% | F | F |
This chart stops at the first F. The calculator above builds the full chart for any test size.
Full charts for common test sizes, each with how many questions you can miss for every letter: 10 questions, 15 questions, 20 questions, 25 questions, 30 questions, 33 questions, 40 questions, 50 questions, 75 questions, 100 questions.
What real schools do: rounding and half points
The US has no national grading standard, so the same score can land in different places. Take a made-up 89.5 on a 100-point test. These rules cover course grades, not single tests:
- Florida's statute prints whole-number ranges and no rounding rule, so 89.5 falls between B (80-89) and A (90-100).
- The Johns Hopkins School of Nursing rounds final course grades to a whole number, so 89.5 becomes 90, an A-.
- Purdue Global's undergraduate table runs B+ up to 89.99, so 89.5 stays a B+.
This tool keeps the exact percent unless you check My teacher rounds .5 up. On the 10-point scale, 89.5 is a B with the box off and an A with it on.
We found no school rule on half points. A 2005 federal overview says classroom teachers typically decide grades, so ask yours. Made-up example: 2 wrong plus half credit on a third question is 2.5 wrong. On 20 questions, 17.5 ÷ 20 × 100 = 87.5%. Set Step to Half to add those rows, or type 2.5 in Quick lookup.
Quiz grades and points-based tests
A quiz works the same way. Made-up example: 1 wrong on an 8-question quiz is 7 ÷ 8 × 100 = 87.5%.
If questions carry different points, use points. Enter the total in Number of questions or points, then type the points lost under Questions wrong. Made-up example: 7 points lost on a 50-point test is 43 ÷ 50 × 100 = 86%.
This tool scores one test at a time. To combine scores, use the Grade Calculator or the Weighted Grade Calculator.
Print a chart for your class
Set your test size, scale and step, then press Print chart. The chart opens on its own page with a Print button. A Whole step fits on one page. Half or Quarter steps on a long test can take more pages. Export CSV saves the same rows as a file, and Copy link gives you a link to this setup.
Why this may not match your gradebook
Your gradebook shows a lower grade
Check the scale first. A 90% is an A on the 10-point scale and an A- on the Plus/minus scale. Then check the points, because this tool counts every question the same unless you enter points.
Your gradebook shows a higher grade
Your teacher may have added a curve or bonus points. This tool does neither, and scores stop at 100%. The How to Curve Grades Fairly guide compares methods.
You are off by less than a point
Check rounding. An 87.5% shows as 88% with Whole number picked. Set Show percent as to One decimal to see 87.5%.
Test grade calculator FAQ
What is 17 out of 20 as a percent?
85%. Divide 17 by 20, then multiply by 100.
How many questions can I miss and still get an A?
On a 20-question test on the 10-point scale, 2. That leaves 90%. On 25 questions it is also 2, because 3 wrong is 88%.
Is this a test score calculator or a quiz grade calculator?
Both. It works for any test or quiz from 1 to 200 questions or points.
Can a score go above 100%?
Not here, because Quick lookup stops at 0 wrong. The Grade Calculator handles extra credit.
Related tools and guides
- Grading Scale: See how percents turn into letter grades, and set your own scale.
- Grade Calculator: Find your current grade from your assignments.
- How to Curve Grades Fairly: Methods Compared
- How to Set Up a Gradebook Students Can Check
- Rubric Grading: Why 2 out of 4 Need Not Mean 50%
Sources
- Chapter 1003 Section 437 - 2026 Florida Statutes - The Florida Senate
- Grading Policy | Johns Hopkins University Academic Catalogue
- Academic Grades and Marks
- Education in the United States: A Brief Overview (U.S. Department of Education, September 2005)
Every rule these tools use, and how each number is worked out, is on How we calculate.
Cite this page
GradeCat. (2026, November 4). Test Grade Calculator. https://gradecat.com/test-grade-calculator/
Last updated 2026-11-04. Results are estimates, not official grades. Your school may use different rules. Found a wrong result? Report it.