Test Grade Calculator
Convert correct answers or earned points into a percentage score and letter grade for quizzes, midterms, and final exams, with standard or custom grading scales.
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Calculation Examples
📋Steps to Calculate
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Select your input method: question-based (correct vs. total) or point-based (earned vs. maximum).
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Enter your results (e.g., 18 out of 20 questions, or 45 out of 50 points).
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Review the percentage score and the matching letter grade on the default scale.
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Adjust the grading scale thresholds if your institution uses a custom curve or a stricter standard.
Mistakes to Avoid ⚠️
- Counting questions that the teacher dropped or that were never graded in the total, which lowers the percentage.
- Entering points lost where the calculator expects points earned, which shows a failing result for a passing performance.
- Using the 10-point scale for a course that uses a 7-point scale (A starts at 93%). Always confirm your school's thresholds.
- Assuming scores round up at a boundary: 89.5% becomes 90% only if the school rounds, and many do not. A fraction of a point can change the letter.
Who Benefits from This Tool📊
Students tracking GPA: Run "what-if" checks, such as how many questions you can miss on a 40-question exam and still earn 80% (8 questions), before you sit it.
Teachers and graders: Convert raw scores to percentages and letter grades for a full class without long division or lookup tables.
Tutors and homeschool educators: Apply one clear grading standard across subjects and assessment formats.
Test prep and progress tracking: Put practice tests, quizzes, and assignments on one percentage scale so you can see a trend over a course.
Questions and Answers
Can I use this for midterms, finals, and standardized tests?
Yes for coursework, and with a caveat for standardized tests. Midterms, finals, quizzes, and homework all use the same fraction of a maximum. Standardized tests such as the SAT, ACT, and AP convert performance into scaled scores, and the digital SAT adapts the second module to your first-module result, so a simple percentage does not predict the reported score. Use this tool for raw-score-to-grade mapping in class.
How do I calculate a test grade from correct answers and total questions?
Divide the correct answers by the total questions and multiply by 100: \(\text{Percent} = (\text{correct} \div \text{total}) \times 100\). With 16 correct out of 20, \((16 \div 20) \times 100 = 80\%\), which is a B- on the 10-point plus/minus scale and a B on the plain 10-point scale. The calculator does this for you, so you can spend the time on the questions you missed.
How does the points-based grading system work in this tool?
Enter the points you earned and the maximum possible points, and the calculator applies \((\text{earned} \div \text{total}) \times 100\), then maps the result to the chosen scale. This handles tests where questions carry different weights. A 10-point essay and a 2-point multiple-choice question add their real point values to the total, so a bad essay costs you five times as much as a missed multiple-choice question.
Is 18 out of 20 a good grade?
Yes, 18 out of 20 is 90%, which is an A- on the 10-point plus/minus scale and an A on the plain 10-point scale. It usually shows strong mastery with small gaps. In a class averaging 75%, a 90% is well above the mean. Whether it is enough for you depends on any minimum grade tied to a scholarship, program admission, or academic standing.
What are the most common test score percentages and their letter grades?
Reference table for the 10-point plus/minus scale (A 93-100, A- 90-92, B+ 87-89, B 83-86, B- 80-82, C+ 77-79, C 73-76, C- 70-72, D 63-66). The exact boundaries vary by school, so treat it as a guide.
| Score Ratio | Percentage | Letter Grade | Standing |
|---|---|---|---|
| 20 / 20 | 100% | A+ | Perfect |
| 19 / 20 | 95% | A | Excellent |
| 18 / 20 | 90% | A- | Excellent |
| 17 / 20 | 85% | B | Very good |
| 16 / 20 | 80% | B- | Good |
| 15 / 20 | 75% | C | Average |
| 14 / 20 | 70% | C- | Satisfactory |
| 12 / 15 | 80% | B- | Good |
| 11 / 15 | 73.3% | C | Average |
| 45 / 50 | 90% | A- | Excellent |
| 33 / 50 | 66% | D | Below average |
What formula is used to calculate a grade percentage?
The formula is: \[\text{Grade (\%)} = \frac{\text{Score Achieved}}{\text{Maximum Possible Score}} \times 100\] It applies to question-based and point-based tests alike, and scales or curves come after it. For a weighted course grade, multiply each category percentage by its weight and add: \[\text{Final} = \sum_i w_i \, p_i\] For example, a midterm of 85% at 30%, a final of 78% at 40%, and assignments of 92% at 30% give \(0.30 \times 85 + 0.40 \times 78 + 0.30 \times 92 = 84.3\%\).
What is a test grade calculator and how does it help?
A test grade calculator converts raw results (correct answers or earned points) into a percentage and a letter grade. Division with awkward numbers is error-prone, and scales map percentages to letters differently, so a tool removes both problems. Students can see what a target grade requires, and teachers can replace repeated arithmetic with one consistent calculation.
What is the difference between a percentage score and a letter grade?
A percentage is a precise measure of how much you answered correctly, such as 87%, and a letter grade is a label a school assigns to that percentage. The same 87% is a B+ on the 10-point plus/minus scale and a B on the 7-point scale, where B covers 85-92%. The math fixes the percentage, and your institution's scale decides the letter.
Disclaimer: This calculator is designed to provide helpful estimates for informational purposes. While we strive for accuracy, financial (or medical) results can vary based on local laws and individual circumstances. We recommend consulting with a professional advisor for critical decisions.