Test Grade Calculator
Enter the number of questions and how many you got wrong. Get your test score as a percentage and letter, and see how many you can miss for each grade.
- Percent and letter
- Number wrong or right
- Half points
- Grading chart
Your test
Test score
85%
B17 of 20 right, 3 wrong. Each question or point counts for 5%.
Most you can miss for each grade
- A+0 wrong
- A1 wrong
- A-2 wrong
- B+2 wrong
- B3 wrong
- B-4 wrong
- C+4 wrong
- C5 wrong
- C-6 wrong
- D+6 wrong
- D7 wrong
- D-8 wrong
Grading chart for 20 questions
| Wrong | Right | Score | Grade |
|---|---|---|---|
| 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 |
Grading scale: Plus/minus with A+ (A+ 97, A 93, A- 90)Change
A grade at or above a cutoff gets that letter. Edit any number to match your syllabus; the scale is used by every tab and saved on this device.
Your classes and scores are saved in this browser only. Nothing is sent to a server.
What is a test grade calculator?
A test grade calculator turns a raw test result, such as 3 wrong out of 20, into a percentage and letter grade. The math is simple (correct answers ÷ total × 100), but it is easy to get wrong in a hurry, especially with odd totals like 23 questions or half-credit answers. This calculator works with questions or points, with the number wrong or the number right, and with the grading scale your school uses. The chart below the result lists every possible score, so you can see how many questions you can miss and still get an A, a B or a passing grade.
How to calculate a test score
- Open the Test score tab and enter the number of questions or total points on the test.
- Enter how many were wrong, or switch to Number right if that is easier. Decimals work for half credit.
- Read the percentage and letter grade.
- Use the grading chart below to see the score for every possible number wrong, then print it if you are grading a set of tests.
Why use this test grade calculator
- Answers as you typeNo Calculate button and no page reloads. Change any number and every result updates in the same moment.
- A full grading chartEnter the number of questions and see the percentage and letter for every possible number wrong, with half points if you need them. Print it and keep it next to the stack of tests.
- Your school’s grading scaleChoose plus/minus with or without A+, or a simple 10-point scale, then edit any cutoff to match your syllabus. Every result updates at once.
- Points and half creditUse points instead of questions, and decimals like 2.5 wrong for partial credit. The chart can step in half points.
- Three calculators in oneCourse grade, final exam and test score are tabs on the same page and share one grading scale. Your course grade can be sent to the final exam tab in one click.
- Saved on your device, privateYour classes and scores are kept in this browser, so they are still there next time. Nothing is sent to a server and there is no account to create.
Who uses a test score calculator
- Checking a test before it is returned. Count the questions you are unsure about and see the lowest score you could get.
- How many can I miss?. Before a quiz, check how many questions you can get wrong and still keep an A or pass.
- Grading tests and quizzes. Teachers can turn a number wrong into a percentage and letter in a second, or print the chart for a whole stack of papers.
- Practice tests. Score SAT, ACT, AP or driving test practice sections quickly and track your percentage.
- Parents following progress. Enter the scores from the parent portal and see what your child needs on the rest of the term, explained in plain numbers.
- Adding a test to your class grade. Paste the test score into the Course grade tab to see how it changes your overall grade.
Grade formulas, with examples
These are the formulas the calculator uses. Weights are percentages, or decimals where the formula says so (25% = 0.25).
- Weighted grade
- (score₁ × weight₁ + score₂ × weight₂ + …) ÷ (weight₁ + weight₂ + …)
- Example: (95 × 20 + 88 × 15 + 82 × 25 + 90 × 15) ÷ 75 = 88.27%
- Points grade
- total points earned ÷ total points possible × 100
- Example: 405 ÷ 450 × 100 = 90%
- Score needed on the final
- (target - current × (1 - final weight)) ÷ final weight
- Example: (90 - 88 × 0.75) ÷ 0.25 = 96%
- Grade after the final
- current × (1 - final weight) + final score × final weight
- Example: 88 × 0.75 + 80 × 0.25 = 86%
- Test score
- (questions - wrong) ÷ questions × 100
- Example: (20 - 3) ÷ 20 × 100 = 85%
Letter grade scale: percentages for A to F
Most US high schools and colleges use the plus/minus scale below. Some stop at A (no A+), and many high schools use a simple 10-point scale (A 90, B 80, C 70, D 60). Your syllabus has the final word, and you can change every cutoff in the calculator.
| Letter | Percentage | Letter | Percentage |
|---|---|---|---|
| A+ | 97 to 100 | C | 73 to 76.99 |
| A | 93 to 96.99 | C- | 70 to 72.99 |
| A- | 90 to 92.99 | D+ | 67 to 69.99 |
| B+ | 87 to 89.99 | D | 63 to 66.99 |
| B | 83 to 86.99 | D- | 60 to 62.99 |
| B- | 80 to 82.99 | F | Below 60 |
| C+ | 77 to 79.99 |
How this compares with other grade calculators
A summary of what popular free grade calculators offered in October 2026, based on their public pages: general calculator sites such as Calculator.net and Omni, single-purpose final grade calculators such as RogerHub, and the many small weighted grade sites. Features change, so check before relying on one.
| Feature | This calculator | General calculator sites | Final grade calculators | Weighted grade sites |
|---|---|---|---|---|
| Weighted categories | Yes, any number | Yes | No (final only) | Yes |
| Points-based grading | Yes | Yes | Separate mode | Yes |
| Score needed for every letter at once | Yes | One target | One target | One target |
| Weights that do not add to 100 | Handled and explained | Partly | Not applicable | Partly |
| Scores as 44/50 or B+ | Yes, in the same box | Letters via a setting | No | Letters via a setting |
| Test score and grading chart | Yes, printable | Separate page | No | Separate page |
| Editable grading scale | Yes, three presets | Some | Not applicable | Some |
| Saves your classes | Yes, on your device | Rarely | No | Rarely |
More tools for school
Turn your letter grades into a grade point average with the GPA calculator, check percentages with the percentage calculator, or average a list of scores with the average calculator. For studying, try the Pomodoro timer, write equations with the math editor and format sources with the citation generator. See every tool on the student tools page.
Example: 3 wrong out of 20
20 questions, 3 wrong, so 17 correct. 17 ÷ 20 × 100 = 85%, which is a B on the plus/minus scale and a B on a 10-point scale. The chart shows that 2 wrong (90%) would have been an A-, and 4 wrong (80%) is the lowest score that still earns a B-.
What to expect from the result
The calculator treats every question as worth the same unless you enter points. If questions have different values, enter total points and points lost instead. Curves, bonus questions and penalties for guessing are not applied.
Test Grade Calculator questions
How do I calculate a test grade?
Divide the number of correct answers by the total number of questions and multiply by 100. With 3 wrong out of 20, 17 ÷ 20 × 100 = 85%, which is a B on the standard scale.
How many questions can I miss and still get an A?
On a 90% A, you can miss 10% of the questions: 2 out of 20, 5 out of 50 or 10 out of 100. Enter the number of questions and the grading chart shows the exact cutoff for every letter on your scale.
What is 17 out of 20 as a percentage?
17 ÷ 20 = 0.85, so 17 out of 20 is 85%, a B. Some other common scores: 18/20 = 90%, 15/20 = 75%, 22/25 = 88% and 45/50 = 90%.
Can I enter half points?
Yes. Enter a decimal such as 2.5 for the number wrong, and choose half points for the chart to see every score in steps of 0.5.
Does a test score change my class grade?
It depends on how much the test is worth. Add it to the Course grade tab under its category, such as Tests 40%, to see your updated class grade.