How to use the test grade calculator
- Choose Questions or Points. Use Questions when every question is worth the same. Use Points when questions carry different marks, such as a 40-point test.
- Enter the total and either the number wrong or the number right. Decimals work for partial credit, such as 2.5 wrong.
- Pick a letter scale and rounding. The default is a common A to F scale rounded to a whole percent. You can switch to plus and minus grades or type your own cut-offs.
It is meant to be an easy grade calculator for a stack of papers: the percent and letter update as you type, with a list of the most a student can miss for each letter. Below the calculator is the full grading chart for the test, which you can print on its own or copy into a spreadsheet. As a quiz grade calculator it works the same way: a 10-question quiz is simply a test with a total of 10.
How a test grade is worked out
The grade is the share of the test the student got right, as a percent:
Percent = (total − number wrong) ÷ total × 100
On a 25-question test with 3 wrong, the student got 22 right. 22 ÷ 25 = 0.88, so the grade is 88%. With points it is the same sum: points earned divided by points possible, so 35.5 out of 40 is 88.75%. That is all "points to percentage" means.
When the answer is not a whole number, the calculator rounds it the way you choose. A 26-question test with 3 wrong is 23 ÷ 26 = 88.4615...%, which shows as 88% rounded to a whole number or 88.5% to one decimal. The letter comes from the rounded percent, the one you would write on the paper, and the exact figure is shown under the result.
A printable grading chart for any test
Many teachers keep a chart beside the pile of papers: one row for each number wrong, with the percent and letter already worked out. The E-Z Grader is a well-known paper slide chart sold to teachers; this calculator is not connected with it, but does a similar job. This calculator builds that chart for whatever total you enter, from all right to all wrong. Tick Half points in the chart to add rows for 0.5, 1.5 and so on.
Here is the top of the chart for a 20-question test, where each question is worth 5%:
| Wrong | Right | Percent | 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 |
Print chart prints only the chart, laid out in columns with the test name at the top, so a long test still fits on one or two pages. Copy chart copies it as rows and columns that paste straight into Excel or Google Sheets.
How many can a student miss?
The result panel lists the most a student can get wrong and still earn each letter. For a 25-question test, each question is worth 4%, so on the common A to F scale:
| Letter | Most wrong | Lowest score |
|---|---|---|
| A (90% and up) | 2 | 92% |
| B (80% and up) | 5 | 80% |
| C (70% and up) | 7 | 72% |
| D (60% and up) | 10 | 60% |
With half points on, an A allows 2.5 wrong (exactly 90%) and a C allows 7.5. Students can use the same list before a test to see how many they can miss.
Letter grade scales
A, B, C, D, F (10-point). This is a common scale, but schools set their own. A is 90 to 100, B 80 to 89, C 70 to 79, D 60 to 69 and F below 60. The US National Center for Education Statistics uses these cut-offs when it standardizes high school transcripts, and notes that grade information on transcripts can "vary considerably among schools, districts and states".
With plus and minus grades. This option uses the scale Green Bay Area Public Schools in Wisconsin publishes on its website: A 93 to 100, A- 90 to 92, B+ 87 to 89, B 83 to 86, B- 80 to 82, C+ 77 to 79, C 73 to 76, C- 70 to 72, D+ 67 to 69, D 63 to 66, D- 60 to 62 and F 0 to 59. On it, the 88% above is a B+. Other districts draw the plus and minus lines differently.
My own cut-offs. If your school uses something else, type each letter and the lowest percent for it. For a 7-point scale you might enter A 93, B 85, C 77, D 70 and F 0. The lowest letter needs a cut-off of 0 so every score gets a letter.
Rounding and partial credit
Rounding can change a letter. On a 200-point test, a student who loses 21 points scores 179 ÷ 200 = 89.5%. Rounded to a whole number that is 90%, an A. Kept to one decimal it is 89.5%, a B on the 10-point scale. Neither is wrong; pick the rule your school or syllabus uses and use it for the whole class.
For partial credit, enter the points lost with decimals. A student who loses 4.5 points on a 40-point test has 35.5 ÷ 40 = 88.75%, which is 89% as a whole number (a B+ on the plus and minus scale) or 88.8% to one decimal.
Test grades in Excel or Google Sheets
Put the total in B1 and each student's number wrong in column A from A3 down. In B3, enter:
=ROUND(($B$1-A3)/$B$1*100, 0)
and fill it down. With 25 in B1 and 3 in A3 the result is 88. Change the last 0 to 1 for one decimal. Microsoft describes ROUND as a function that "rounds a number to a specified number of digits", and Google's help says it "rounds a number to a certain number of decimal places according to standard rules". If column A holds the number right instead, use =ROUND(A3/$B$1*100, 0).
Questions and answers
How do I calculate a test grade?
Take the number right, divide by the total and multiply by 100. On a 25-question test with 3 wrong, that is 22 / 25 x 100 = 88%. With points, divide the points earned by the points possible.
How many questions can I miss and still get an A?
On a 90% cut-off, up to 10% of the test. That is 2 questions on a 20 or 25-question test and 5 on a 50-question test. Enter the total and the calculator lists the most you can miss for every letter.
Is 89.5% an A?
It depends on rounding. Rounded to a whole number, 89.5% becomes 90%, an A on a 10-point scale. Kept to one decimal it stays 89.5%, a B. Your school or teacher decides which rule applies.
What is an E-Z Grader?
The E-Z Grader is a paper slide chart sold to teachers that turns the number wrong into a percent. This calculator is not connected with it, but does a similar job for any total and prints the whole chart, with letters on the scale you choose.
Can I print the grading chart?
Yes. Print chart prints only the chart, in compact columns with the test name you typed. Copy chart copies it for a spreadsheet.
Which grading scale should I use?
The one your school or district sets. The 10-point A to F scale is common, many schools use plus and minus grades, and some use a 7-point scale or other cut-offs, which you can type in yourself.
Sources
Checked on 8 October 2026. If a rule has changed, please tell us.