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Easy grader: a free grading calculator and chart for teachers

Enter the number of questions and how many a student got wrong: the easy grader shows the percentage and the letter grade at once, and the chart for every possible score. Free, no sign-up, and you can print it.

Updated October 2026

17 of 20 correct

85%B

Score shown as

Grading chart for 20 questions

  1. −0 wrong, 20 correct:100%A
  2. −1 wrong, 19 correct:95%A
  3. −2 wrong, 18 correct:90%A
  4. −3 wrong, 17 correct:85%B
  5. −4 wrong, 16 correct:80%B
  6. −5 wrong, 15 correct:75%C
  7. −6 wrong, 14 correct:70%C
  8. −7 wrong, 13 correct:65%D
  9. −8 wrong, 12 correct:60%D
  10. −9 wrong, 11 correct:55%F
  11. −10 wrong, 10 correct:50%F
  12. −11 wrong, 9 correct:45%F
  13. −12 wrong, 8 correct:40%F
  14. −13 wrong, 7 correct:35%F
  15. −14 wrong, 6 correct:30%F
  16. −15 wrong, 5 correct:25%F
  17. −16 wrong, 4 correct:20%F
  18. −17 wrong, 3 correct:15%F
  19. −18 wrong, 2 correct:10%F
  20. −19 wrong, 1 correct:5%F
  21. −20 wrong, 0 correct:0%F

How to use the easy grader

  1. Set the number of questions on the test.
  2. Enter how many a student got wrong to see their score and letter grade, or read it straight off the chart.
  3. Print the chart and keep it next to the stack of tests.

How the score is calculated

Score = correct answers ÷ number of questions × 100. With 3 wrong out of 20, that is 17 ÷ 20 × 100 = 85%.

  • Half points: with half points on, a question with partial credit counts as half wrong.
  • Rounding: scores are rounded to the nearest whole number (or one decimal), with halves rounded up, so 87.5% shows as 88%. Some schools don't round; check your policy.
  • Letter grades use the rounded score, the one you write on the paper.

Which grading scale?

The easy grader includes the three scales most US schools use: the 10-point scale (A from 90), the same scale with plus and minus grades, and the stricter 7-point scale (A from 93). The full tables, with GPA points, are in the grading scale guide.

When questions aren't worth the same

An easy grader assumes every question is worth the same. When they aren't, add up the points earned and divide by the points possible: 34 of 40 points is 85%, whatever the number of questions.

Counting wrong answers is the easy part

The written answers are what take the evening. Mentora grades them against your rubric as students turn the test in, scores the multiple choice too, and tells you what to reteach.

Early access, in small batches. One email when your spot is ready; nothing else.

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Frequently asked questions

What is an easy grader?

An easy grader, sometimes called an EZ grader, is a chart that turns the number of wrong answers on a test into a percentage score. Set the number of questions, and it shows the score for every possible number wrong, so you can grade a stack of tests without a calculator.

Is this easy grader free?

Yes. It runs in your browser, with no account and no limits, and you can print the chart.

How do I calculate a test score percentage?

Divide the number of correct answers by the number of questions and multiply by 100. On a 20-question test with 3 wrong, that is 17 ÷ 20 × 100 = 85%.

How do I grade with half points?

Turn on half points. The chart then counts wrong answers in steps of 0.5, so a question with partial credit costs half a question: 2.5 wrong on 20 questions is 87.5%, or 88% rounded.

What letter grade is 85%?

A B on the common 10-point scale (80–89%), on the plus-and-minus scale (83–86%) and on the 7-point scale (85–92%). Your school's scale is the one that counts.

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