Your result will appear here
Fill in the fields and press Calculate.
Grading a stack of papers is just the same small calculation over and over: correct out of total, as a percentage, then a letter. This calculator does it instantly. Enter how many questions the test had and how many a student got wrong, and get the score and letter grade — the classic “EZ grader” in one step.
How is it calculated?
Score and letter
| Step | Calculation |
|---|---|
| Correct | total − wrong |
| Percentage | correct ÷ total × 100 |
| Letter | mapped from the percentage |
The letter uses the standard US scale:
| Percentage | Letter |
|---|---|
| 90–100% | A |
| 80–89% | B |
| 70–79% | C |
| 60–69% | D |
| Below 60% | F |
Grade by number wrong
Entering the number *wrong* rather than the number right is how teachers actually grade — you count the red marks, not the correct answers. On a 20-question test, 3 wrong means 17 right, which is 85% — a B.
Scales vary
The A–F cutoffs above are the common US convention, but institutions differ: some use +/− bands, others set an A at 93% or use entirely different systems. Treat the letter as the standard-scale result and apply your own school’s cutoffs if they differ.
Worked example
A quiz has 20 questions and a student misses 3. Correct answers: 20 − 3 = 17. Percentage: 17 ÷ 20 × 100 = 85%, which lands in the 80–89% band, so the grade is a B. Miss just one more (4 wrong) and it’s 16 ÷ 20 = 80% — still a B, but right on the boundary. One more after that drops it to 75%, a C.
FAQ
How do I calculate a test grade?+
Divide the number of correct answers by the total number of questions and multiply by 100 for the percentage, then map it to a letter. This tool takes the total and the number wrong, works out the rest, and shows the percentage and letter grade instantly.
What letter grade is each percentage?+
On the standard US scale: 90–100% is an A, 80–89% a B, 70–79% a C, 60–69% a D and below 60% an F. Some schools add +/− bands or set different cutoffs, so check your institution’s scale if it varies.
Why enter the number wrong instead of the number right?+
Because that’s how grading actually works — you count the mistakes on the page. On a 25-question test it’s quicker to note 4 wrong than to tally 21 correct. The calculator converts wrong answers into the score for you.
Does this handle weighted grades or multiple assignments?+
No — this is a single-test percentage-and-letter grader (the EZ-grader style). For a course grade made of assignments with different weights, you’d combine each component’s score by its weight; that’s a separate calculation.
Can I use it for any number of questions?+
Yes — it works for any total from 1 up to 10,000 questions, and the percentage is exact regardless of the count. A 3-wrong result is 85% on a 20-question test but 97% on a 100-question test, and the tool reflects that.