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EZ Grader Calculator
Turn total questions and wrong answers into a percentage, letter grade and full grading chart.
Teachers17 of 20 correct · 3.0 grade points on the US Standard (90/80/70/60) scale
Grading chart for 20 questions
| Wrong | Correct | Percentage | Grade |
|---|---|---|---|
| 0 | 20 | 100.0% | A |
| 1 | 19 | 95.0% | A |
| 2 | 18 | 90.0% | A |
| 3 | 17 | 85.0% | B |
| 4 | 16 | 80.0% | B |
| 5 | 15 | 75.0% | C |
| 6 | 14 | 70.0% | C |
| 7 | 13 | 65.0% | D |
| 8 | 12 | 60.0% | D |
| 9 | 11 | 55.0% | F |
| 10 | 10 | 50.0% | F |
| 11 | 9 | 45.0% | F |
| 12 | 8 | 40.0% | F |
| 13 | 7 | 35.0% | F |
| 14 | 6 | 30.0% | F |
| 15 | 5 | 25.0% | F |
| 16 | 4 | 20.0% | F |
| 17 | 3 | 15.0% | F |
| 18 | 2 | 10.0% | F |
| 19 | 1 | 5.0% | F |
| 20 | 0 | 0.0% | F |
The EZ Grader replaces the sliding grading wheel teachers have used for decades. Enter how many questions a test had and how many a student missed, and the calculator returns the percentage score, the letter grade and the GPA points, together with a complete grading chart for that test size. It works for a 5-question pop quiz or a 100-question final, and you can switch between the US standard scale, the US plus/minus scale, the Canadian scale and the Australian HD to F scale.
How to use the EZ Grader Calculator
- Enter the total number of questions on the test.
- Enter how many answers the student got wrong.
- Choose the grading scale your school uses.
- Read the percentage and letter grade, and use the chart row for the next student.
Formula
The letter grade is then read from the grading scale you selected. On the US standard scale, 90% and above is an A, 80-89% a B, 70-79% a C, 60-69% a D and below 60% an F.
Worked example
A spelling test has 20 questions and a student misses 3. Correct answers = 20 - 3 = 17. Percentage = 17 / 20 x 100 = 85%. On the US standard scale that is a B, worth 3.0 GPA points. The chart under the calculator shows every other score for a 20-question test, so the next paper takes seconds to mark.
Good to know
Paper tests are still graded by hand in most classrooms, and the arithmetic is where small mistakes creep in: one mis-added question can move a student across a grade boundary. A chart-based grader removes that risk because every possible score for the test size is computed once, consistently. If your school rounds percentages, check the result before rounding; a score of 89.6% is a B on most scales until a rounding policy is applied. Teachers who grade a whole class set often keep the chart for their most common test sizes, such as 10, 20, 25 and 50 questions, printed and pinned beside the desk.
US grading scale reference
The table below is the US plus/minus scale used across this site. Where this tool offers other scales, the Canadian scale sets an A from 85% with a pass at 50%, and the Australian scale uses the bands HD (85%+), D (75-84%), C (65-74%), P (50-64%) and F (below 50%) on a 7.0 GPA.
| Letter grade | Percentage | GPA points |
|---|---|---|
| A+ | 97–100% | 4.0 |
| A | 93–96% | 4.0 |
| A- | 90–92% | 3.7 |
| B+ | 87–89% | 3.3 |
| B | 83–86% | 3.0 |
| B- | 80–82% | 2.7 |
| C+ | 77–79% | 2.3 |
| C | 73–76% | 2.0 |
| C- | 70–72% | 1.7 |
| D+ | 67–69% | 1.3 |
| D | 63–66% | 1.0 |
| D- | 60–62% | 0.7 |
| F | 0–59% | 0.0 |
Frequently asked questions
What is an EZ grader?
An EZ grader is a chart or calculator that converts the number of wrong answers on a test into a percentage and letter grade. It began as a cardboard sliding wheel; this online version builds the same chart instantly for any number of questions.
How do I grade a 20-question test quickly?
Each question on a 20-question test is worth 5%. A student with 1 wrong scores 95% (A), 2 wrong scores 90% (A), 3 wrong scores 85% (B), and so on. The chart on this page lists all 21 possible scores.
Does the EZ grader work with points instead of questions?
This tool is built for question counts. If your test is marked in points, use the Test Grade Calculator instead, which accepts points earned and points possible, including half points.
Which grading scale should I choose?
Use US Standard if your school grades on whole letters with 90/80/70/60 cut-offs, US Plus/Minus if it awards grades like B+ and A-, Canada for the Canadian percentage bands, and Australia for HD, D, C, P and F results.
Can I print the grading chart?
Yes. Set the number of questions, then print the page from your browser. The chart prints as a clean table you can keep with your mark book for that test size.
Go deeper
Prefer the full walkthrough? Read our guide: What Do Letter Grades Mean? — it explains the method step by step with more worked examples.
Sources & further reading
- Education Week — grading and assessment coverage — Reporting and research on classroom grading practice for K-12 educators.
- ASCD — resources on fair and accurate grading — Professional guidance for educators on assessment and reporting.
Related tools
Last reviewed: November 2026. Results from this calculator are estimates based on the published scales above; your school's recorded grade is the official one.