Easy Grader
Enter the number of questions and get an instant grading chart — the score and letter grade for every number of wrong answers.
| Wrong | Correct | 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 |
How to use the grading chart
Set the number of questions on the test, then read down the chart: each row shows how many wrong answers produce a given percentage and letter grade. Mark a paper, count the crosses, find that row. It is the fastest way to grade a stack by hand, and it removes the arithmetic error that creeps in around paper thirty.
The underlying calculation is simply score = (correct ÷ total) × 100, worked out once for every possible number of wrong answers so you never have to do it per paper.
Why the deduction per question is the number that matters
The single most useful thing a grading chart tells you is how much one mistake costs, and that depends entirely on how many questions you set:
| Questions | Each worth | Wrong answers still scoring 90%+ |
|---|---|---|
| 10 | 10 points | 1 |
| 20 | 5 points | 2 |
| 25 | 4 points | 2 |
| 40 | 2.5 points | 4 |
| 50 | 2 points | 5 |
A ten-question quiz has no B range worth speaking of: one wrong is 90%, two is 80%, three is 70%. Every mistake moves a whole letter grade. If you want a quiz that distinguishes between students rather than sorting them into three coarse buckets, twenty questions is a practical floor.
Setting a test length that grades cleanly
- Question counts that divide into 100 — 10, 20, 25, 50 — give whole-number percentages and are much easier to check by eye.
- Awkward counts such as 13 or 27 produce repeating decimals, so the chart matters more, not less.
- Extra-credit questions work best kept outside the total. Score the test out of the base count, then add the bonus, so the chart stays valid for everyone.
A note on grade cutoffs
The chart uses the standard ten-point scale — A at 90, B at 80, C at 70, D at 60. This is the most widespread convention in US schools but not a universal rule. Some districts set an A at 93, some use a seven-point scale, and many courses add plus and minus bands within each letter. If your school differs, read the percentage column and apply your own cutoffs to it; the percentages themselves are the same either way.
Related tools
Grading one paper rather than a stack? The test grade calculator gives a single score and letter. To turn a set of graded assessments into an overall course grade, use the weighted grade calculator.
Frequently asked questions
How does the easy grader work?
Enter how many questions are on the test. The chart then shows, for each number of wrong answers, the percentage score and letter grade — so you can grade any paper at a glance.
How is the percentage calculated?
Score = (correct answers ÷ total questions) × 100. For example, 18 correct out of 20 is 90%.
What grade scale does it use?
A standard scale (A = 90–100, B = 80–89, C = 70–79, D = 60–69, F below 60). Your school's cutoffs may differ slightly.
How many points is each question worth?
Divide 100 by the number of questions. On a 20-question test each is worth 5 points, on a 25-question test 4 points, on a 50-question test 2 points. That figure tells you immediately how many mistakes a student can afford before dropping a letter grade.
How many questions should a quiz have?
Twenty is a practical floor if you want the grades to distinguish between students. On a ten-question quiz every single mistake moves a whole letter grade — one wrong is 90%, two is 80%, three is 70% — so there is effectively no B range at all.
Should I include extra-credit questions in the total?
It is cleaner not to. Score the test out of the base question count so the chart stays valid for the whole class, then add bonus points on top of the resulting percentage.
What if my school uses different cutoffs?
Read the percentage column and apply your own letter bands to it. The percentages are unaffected by where your school draws the lines — only the letter beside them changes.