Test Grade Calculator
This test grade calculator converts a raw test score — questions right out of questions total — into a percentage and a standard letter grade. Students use it to check a practice test or predict a graded result; teachers use it for fast, consistent scoring. Just enter the two counts and get the percent, the letter, and how many were missed.
Number of questions answered correctly.
Total number of questions on the test.
Test score — B
84%
- Percentage score
- 84%
- Correct answers
- 42
- Missed answersEach missed question cost 2.0 percentage points.
- 8
How it was calculated
- Score: 42 ÷ 50 × 100 = 84.0% (B).
- Missed: 50 − 42 = 8 questions.
How it works
The percent score is (correct answers ÷ total questions) × 100 — the fraction of the test you got right, scaled to a percent.
Each question is worth 100 ÷ total points of percent, so on a 50-question test every miss costs 2 points, while on a 20-question test each miss costs 5.
The letter grade follows the standard US scale: A for 90% and up, B for 80–89%, C for 70–79%, D for 60–69%, F below 60%.
Worked examples
42 right out of 50
42 ÷ 50 × 100 = 84%, a B. The 8 missed questions each cost 2 points (100 ÷ 50), so one more correct answer would have meant an 86%.
17 right out of 20
17 ÷ 20 × 100 = 85%, a B. With only 20 questions, each miss costs 5 full points — small tests punish mistakes heavily.
How to measure
- Count only fully correct answers; decide beforehand whether partial credit counts as correct or as a miss.
- Use the number of questions actually graded — exclude any questions the teacher threw out.
- For practice tests, count strictly (no "I knew that") so the percent predicts the real result.
- If different sections have different point values, convert to total points first instead of counting questions.
Assumptions & limitations
Planning estimate
- Every question is assumed to carry equal weight; weighted sections need a points-based calculation instead.
- The standard US letter scale is applied (A 90+, B 80+, C 70+, D 60+, F below 60); your instructor may curve or use different cutoffs.
- Partial credit is not modeled — count an answer as correct or missed before entering it.
- A score above 100% (extra credit) is allowed and reported as-is.
Frequently asked questions
Divide the number you got right by the total number of questions, then multiply by 100. Getting 42 out of 50 is 42 ÷ 50 × 100 = 84%, a B. This calculator does it instantly and adds the letter grade.
85%, which is a B on the standard scale. Because the test has only 20 questions, each one is worth 5 percentage points, so a single additional correct answer would have raised it to 90% — an A.
Divide 100 by the number of questions. On a 40-question test each question is worth 2.5 points; on a 25-question test each is worth 4 points. The calculator shows this "cost per miss" in the missed-answers row.
For quick checks, yes — but entering each student’s score one at a time is slow for large classes. It works best for spot-checking, practice tests, and verifying gradebook entries.
No. It reports the raw percent and the uncurved letter grade. If your instructor curves, apply the curve to the percent first, then read the letter off the adjusted number.