Grading Calculator
Number wrong to percent and letter grade, with a printable grading chart
To grade a test, divide the number right by the total and multiply by 100. With 3 wrong out of 25, the score is 22 ÷ 25 × 100 = 88%: a B on the standard 10-point scale (A = 90 to 100) or a B+ with plus/minus grades. On a 25-question test every question is worth 4 points.
Last updated October 2026
Method: Score = (total − missed + partial credit) ÷ total × 100. Letters come from a 10-point scale (A 90, B 80, C 70, D 60), a 10-point plus/minus scale (A 93, A- 90, B+ 87 down to D- 60) or a 7-point scale (A 93, B 85, C 77, D 70), applied to the exact score or after rounding half up to a tenth or a whole percent.
Included: Questions or points, number wrong or right, partial credit, custom cutoffs, three rounding rules, the most misses allowed for each letter and a full grading chart in whole or half steps with a print button.
Not included: Weighted category grades, extra credit above 100%, curves, GPA and scaled scores from standardized tests.
✅ Grade a test
Points given back on answers you marked wrong, for example half credit on two questions = 1.
✅ Test score (10-point scale)
🎯 Most questions a student can miss
Counts follow the chart steps (whole questions) and the rounding rule you picked.
📋 Grading chart: 25 questions
10-point scale, exact scores, whole steps. Each question = 4%.
| wrong | right | Score | Grade |
|---|---|---|---|
| 0 | 25 | 100% | A |
| 1 | 24 | 96% | A |
| 2 | 23 | 92% | A |
| 3 | 22 | 88% | Bthis test |
| 4 | 21 | 84% | B |
| 5 | 20 | 80% | B |
| 6 | 19 | 76% | C |
| 7 | 18 | 72% | C |
| 8 | 17 | 68% | D |
| 9 | 16 | 64% | D |
| 10 | 15 | 60% | D |
| 11 | 14 | 56% | F |
| 12 | 13 | 52% | F |
| 13 | 12 | 48% | F |
| 14 | 11 | 44% | F |
| 15 | 10 | 40% | F |
| 16 | 9 | 36% | F |
| 17 | 8 | 32% | F |
| 18 | 7 | 28% | F |
| 19 | 6 | 24% | F |
| 20 | 5 | 20% | F |
| 21 | 4 | 16% | F |
| 22 | 3 | 12% | F |
| 23 | 2 | 8% | F |
| 24 | 1 | 4% | F |
| 25 | 0 | 0% | F |
📏 Your grading scale
| Letter | Score range (%) |
|---|---|
| A | 90 to 100 |
| B | 80 to under 90 |
| C | 70 to under 80 |
| D | 60 to under 70 |
| F | 0 to under 60 |
Grading calculator: from number wrong to percent and letter grade
A grading calculator turns a raw test result into a percent and a letter grade. Teachers use it as a quick test score calculator: enter the number of questions and the number wrong, and it returns the score, the letter on your grading scale and a chart of every possible result, the same job a cardboard EZ grader does. The math is identical for points: 47 of 55 points is 85.45%.
For a whole course, the Grade Calculator weights homework, quizzes and the final exam, and the GPA Calculator turns letter grades into a grade point average. Use this page for one test, quiz or assignment.
The grading formula: points to percentage
Every test score is a share of the points available. Counting what was missed or counting what was right gives the same answer:
Score % = (total − wrong) ÷ total × 100 Score % = points earned ÷ points possible × 100 With partial credit: (total − wrong + partial) ÷ total × 100 Value of one question = 100 ÷ total The last line explains most of what teachers notice about grading charts. On a 25-question quiz every question is worth 4 points, on a 32-question test 3.125 points and on a 60-question exam 1.667 points, so the same number of misses costs far more on a short quiz.
Worked example: 7 wrong on a 40-question test
A student misses 7 of 40 questions. Each question is worth 2.5 points:
(40 − 7) ÷ 40 × 100 = 33 ÷ 40 × 100 = 82.5% The letter depends on the scale. On the 10-point scale 82.5% is a B, on the plus/minus scale a B- (80 to 82.99), and on a 7-point scale a C, because a B there starts at 85%. The same test also shows how the scales treat the top grade: on the 10-point scale a student may miss 4 questions and keep an A (90%), on the 7-point scale only 2 (95%). Three misses give 92.5%, just short of 93, unless your school rounds to the nearest whole percent, in which case 92.5% becomes 93% and an A.
Worked example: partial credit on a 120-point exam
A final exam is worth 120 points. Items worth 14 points were marked wrong, but the teacher gave back 1.5 points of partial credit on two short answers. Enter Points, Points missed 14 and Partial credit 1.5:
(120 − 14 + 1.5) ÷ 120 × 100 = 107.5 ÷ 120 × 100 = 89.58% With exact scores that is a B on the 10-point scale and a B+ on the plus/minus scale. Rounded to the nearest tenth it is 89.6%, still a B+. Rounded to the nearest whole percent it becomes 90%, which is an A on the 10-point scale and an A- with plus/minus grades. On the 7-point scale it is a B under every rule. The lowest score that reaches 90% with no rounding at all is 108 of 120, half a point more.
How many questions can be missed for each letter
The table shows the most misses that still earn each letter on the 10-point scale with exact scores, plus the A limit on a 7-point scale. The percent in parentheses is the score at that number of misses.
| Questions | Each worth | A (90%+) | B (80%+) | C (70%+) | D (60%+) | A, 7-point |
|---|---|---|---|---|---|---|
| 12 | 8.333 | 1 (91.67%) | 2 (83.33%) | 3 (75%) | 4 (66.67%) | 0 |
| 16 | 6.25 | 1 (93.75%) | 3 (81.25%) | 4 (75%) | 6 (62.5%) | 1 |
| 24 | 4.167 | 2 (91.67%) | 4 (83.33%) | 7 (70.83%) | 9 (62.5%) | 1 |
| 32 | 3.125 | 3 (90.63%) | 6 (81.25%) | 9 (71.88%) | 12 (62.5%) | 2 |
| 35 | 2.857 | 3 (91.43%) | 7 (80%) | 10 (71.43%) | 14 (60%) | 2 |
| 40 | 2.5 | 4 (90%) | 8 (80%) | 12 (70%) | 16 (60%) | 2 |
| 45 | 2.222 | 4 (91.11%) | 9 (80%) | 13 (71.11%) | 18 (60%) | 3 |
| 60 | 1.667 | 6 (90%) | 12 (80%) | 18 (70%) | 24 (60%) | 4 |
| 75 | 1.333 | 7 (90.67%) | 15 (80%) | 22 (70.67%) | 30 (60%) | 5 |
| 80 | 1.25 | 8 (90%) | 16 (80%) | 24 (70%) | 32 (60%) | 5 |
| 100 | 1 | 10 (90%) | 20 (80%) | 30 (70%) | 40 (60%) | 7 |
The pattern is simple: on the 10-point scale a student can miss 10% of the questions, rounded down, and keep an A, 20% for a B, 30% for a C and 40% for a D. The 7-point column shows how much a stricter scale tightens the top grade: on a 12-question quiz a single miss (91.67%) already costs the A.
An EZ grader chart for a 32-question test
Before spreadsheets, many teachers graded with a cardboard slide chart, often called an EZ grader: slide to the number of questions and read the score for each number wrong. The calculator builds the same chart for any test length and adds the letter. Here is the chart for 32 questions on all three built-in scales, using exact scores; every miss costs 3.125 points.
| Wrong | Right | Score | 10-point | Plus/minus | 7-point |
|---|---|---|---|---|---|
| 0 | 32 | 100% | A | A | A |
| 1 | 31 | 96.88% | A | A | A |
| 2 | 30 | 93.75% | A | A | A |
| 3 | 29 | 90.63% | A | A- | B |
| 4 | 28 | 87.5% | B | B+ | B |
| 5 | 27 | 84.38% | B | B | C |
| 6 | 26 | 81.25% | B | B- | C |
| 7 | 25 | 78.13% | C | C+ | C |
| 8 | 24 | 75% | C | C | D |
| 9 | 23 | 71.88% | C | C- | D |
| 10 | 22 | 68.75% | D | D+ | F |
| 11 | 21 | 65.63% | D | D | F |
| 12 | 20 | 62.5% | D | D- | F |
| 13 | 19 | 59.38% | F | F | F |
Three rows stand out. Three wrong (90.63%) is an A on the 10-point scale but a B on the 7-point scale. Five wrong (84.38%) is a B on the 10-point scale and a C on the 7-point scale. Ten wrong (68.75%) still earns a D+ with plus/minus grades but is already an F on the 7-point scale, where a D starts at 70. From 13 wrong on, every scale gives an F.
10-point, plus/minus and 7-point grading scales
There is no national grading scale in the United States; states, districts, schools and individual instructors set their own, so every scale here is a convention, not a rule. The plain 10-point scale (90, 80, 70, 60) is also the one the National Center for Education Statistics uses to standardize high school transcripts unless a school documents other equivalents, and it matches the straight 10-point scale on our Grade Calculator. Plus/minus cutoffs vary more: some schools add an A+ from 97, as the Grade Calculator does, while the plus/minus scale here starts a full A at 93. Used as a grading scale calculator, the tool covers the three common cases, and Custom handles everything else.
| Letter | 10-point | 10-point with plus/minus | 7-point |
|---|---|---|---|
| A | 90-100 | A 93-100, A- 90-92 | 93-100 |
| B | 80-89 | B+ 87-89, B 83-86, B- 80-82 | 85-92 |
| C | 70-79 | C+ 77-79, C 73-76, C- 70-72 | 77-84 |
| D | 60-69 | D+ 67-69, D 63-66, D- 60-62 | 70-76 |
| F | below 60 | below 60 | below 70 |
Ranges are shown in whole percent; with exact scores each band runs up to, but not including, the next cutoff, so 89.99% is still a B. South Carolina shows how much the choice matters. Its statewide Uniform Grading Policy used a 7-point scale until the State Board of Education voted unanimously in April 2016 to move high school courses to a 10-point scale starting in 2016-17. The Department of Education's recommendation cited college admissions and scholarships and noted that all surrounding states already used 10 points; its presentation gave the example of a 92 that counted as an A for a Georgia applicant and a B for a South Carolina applicant to the same university.
Rounding: when does 89.5% become an A?
Gradebooks either keep the exact score or round it before the letter is assigned, and the choice only matters near a cutoff. The calculator offers three rules, all rounding half up:
- Exact: no rounding. 89.99% is a B on the 10-point scale.
- Nearest tenth: 89.95% becomes 90.0% and an A; 89.94% becomes 89.9% and stays a B.
- Whole percent: 89.5% becomes 90% and an A; 89.49% becomes 89%.
Round once, from the exact score. Rounding 89.45% to a tenth first (89.5%) and then to a whole percent (90%) turns a B into an A that neither rule alone would give. Whatever your policy, state it in the syllabus and apply it to every student the same way.
How to use this grading calculator
Choose whether the test is scored in questions or points, enter the total, then enter either the number wrong or the number right. If you gave partial credit on answers marked wrong, type those points in the optional box. Pick the grading scale (or Custom and your own cutoffs), the rounding rule and the chart steps: whole for multiple choice, half points if you grade in halves.
The result card shows the percent, the letter and the arithmetic. Below it you find the most misses allowed for each letter, the full grading chart with the current result highlighted, and your scale's ranges. Press Print chart to print only the chart.
Who uses a teacher grading calculator
Teachers grading a stack of quizzes use the chart as an answer-key companion, and homeschool parents and tutors use it to apply a consistent scale. Students check whether a returned test was scored correctly or how many questions they can afford to miss on the next one. Department heads compare how a 7-point and a 10-point scale would treat the same results, and corporate trainers grade certification quizzes with a pass mark set through the custom scale.
Key terms
- Raw score: the number of questions right or points earned, before any conversion.
- Percent score: the raw score divided by the total possible, times 100.
- Partial credit: points given for an answer that is partly correct.
- Grading scale: the set of cutoffs that turns a percent into a letter.
- Cutoff: the lowest percent that earns a letter, such as 90 for an A on the 10-point scale.
- Plus/minus grading: splitting each letter into three bands, such as B+, B and B-.
- Grading chart (EZ grader): a table of every possible number wrong with its percent and letter.
What changes the score, and tips for fair grading
- Test length. Each question is worth 100 ÷ total points, so short quizzes swing harder per miss.
- Unequal point values. When items carry different points, grade in Points mode, because a missed 3-point item costs three times as much as a missed 1-point item.
- Dropped questions. Removing a flawed question from a 40-question test and giving everyone credit for it are not the same: with 6 other misses, the first gives 33 of 39 (84.62%), the second 34 of 40 (85%). Pick one method for the whole class.
- Rounding and scale. Decide both before grading, and print the chart so every paper is scored the same way.
Limitations
This tool grades one test at a time. It does not weight categories such as homework and exams (the Grade Calculator does), it caps scores at 100% so extra credit has to be tracked separately, and it does not apply curves or convert letters to GPA points. Built-in scales reflect common US practice, not any particular school's policy.
Related calculators
- For a weighted course grade or the score you need on a final, use the Grade Calculator.
- To turn letter grades and credits into a GPA, use the GPA Calculator.
- For any percent question, such as what share 47 is of 55, use the Percentage Calculator.
- To combine semester GPAs, use the Cumulative GPA Calculator.
- To translate a GPA back to a percent, use the GPA to Percentage Calculator.
- For a class average, median or mode, use the Average Calculator.
Sources
Percent scores and chart values are exact arithmetic; letter cutoffs are conventions. The national transcript convention comes from NCES, and the scale history from the South Carolina Department of Education:
- National Center for Education Statistics, NAEP High School Transcript Study: How is grade point average calculated? (A = 90 to 100, B = 80 to 89, C = 70 to 79, D = 60 to 69, F below 60, unless a school documents other equivalents).
- News release, April 13, 2016: State Board approves a 10-point scale for high school courses from 2016-17 (ed.sc.gov).
- FAQ on the 10-point scale: floors of 90 for an A, 80 for a B, 70 for a C and 60 for a D (ed.sc.gov).
- State Board presentation, Uniform Grading Policy, April 12, 2016: former scale (A 93-100, B 85-92), rationale and the 92 example (ed.sc.gov).
- 10 Point Grading Scale conversion chart (ed.sc.gov).
- South Carolina Uniform Grading Policy (May 14, 2019), including the pre-2016 scale (C 77-84, D 70-76, F 0-69) (ed.sc.gov).
⚠️ Common mistakes & edge cases
Reporting the percent missed
7 wrong out of 40 is 17.5% missed, not a score of 17.5%. The score is the complement, 82.5%. Divide what was right, not what was wrong, when you want the grade.
Taking a flat 2 points per miss
A fixed deduction only works on a 50-question test. On 40 questions, 7 misses at 2 points each gives 86, but each question is really worth 2.5 points and the correct score is 82.5%.
Rounding twice
89.45% rounds to 89% in one step. Rounding to 89.5% first and then to 90% inflates the grade. Always round once, from the exact score.
Dropping a question but still counting it wrong
When a flawed question is removed, the total falls from 40 to 39 and nobody should lose credit on it. A student with 6 other misses scores 33 of 39 (84.62%); still marking the dropped question wrong gives 32 of 39 (82.05%).
Counting questions on a points test
Missing two 3-point items and one 1-point item on a 50-point test is 43 of 50, or 86%. Counting it as 3 wrong out of 30 questions gives 90% and the wrong letter.
Assuming every school uses the same scale
A 92 is an A on a 10-point scale and a B on a 7-point scale. Check the official cutoffs before telling a student what letter a percent earns.
❓ Frequently asked questions
How do teachers calculate a test score from the number wrong?
Subtract the number wrong from the total, divide by the total and multiply by 100. On a 40-question test with 7 wrong: (40 − 7) ÷ 40 × 100 = 82.5%. Each question on that test is worth 100 ÷ 40 = 2.5 percentage points, so every miss lowers the score by exactly 2.5 points.
What is an EZ grader, and does this calculator work the same way?
An EZ grader is the cardboard slide chart many teachers keep on the desk: set the number of questions and it lists the percent for each number wrong. This calculator does the same job for tests of up to 1,000 questions or points (500 with half-point steps), adds the letter grade for your scale, handles partial credit and prints the chart.
How do I convert points to a percentage?
Divide the points earned by the points possible and multiply by 100. A student with 47 of 55 points has 47 ÷ 55 × 100 = 85.45%, a B on the 10-point scale. In the calculator, choose Points and Points earned, then enter 55 and 47.
What grade is 4 wrong out of 45?
41 right out of 45 is 91.11%. That is an A on the standard 10-point scale, an A- on the plus/minus scale and a B on a 7-point scale, where an A starts at 93%. Each question is worth 2.22 points, so a fifth miss drops the score to 88.89%.
How many questions can you miss on a 60-question test and still get an A?
Six on the 10-point scale, because 54 out of 60 is exactly 90%. The plus/minus scale and the 7-point scale both start a full A at 93%, so there the limit is four misses (93.33%). A fifth miss gives 91.67%: an A- with plus/minus grades and a B on the 7-point scale.
What is the difference between a 10-point and a 7-point grading scale?
On a 10-point scale each letter covers ten points: A is 90 to 100, B 80 to 89, C 70 to 79, D 60 to 69 and F below 60. A 7-point scale is stricter: A 93 to 100, B 85 to 92, C 77 to 84, D 70 to 76 and F below 70. South Carolina used the 7-point version statewide until its board adopted a 10-point scale for high school courses starting in 2016-17.
Should 89.5% round up to an A?
Only if your school or syllabus says so. Rounded to the nearest whole percent, 89.5% becomes 90% and earns an A (an A- with plus/minus grades); without rounding it stays a B (B+). The rounding buttons let you match either policy, and the chart shows which scores change letter.
How does partial credit work in this grading calculator?
Enter the points marked wrong as usual, then type the credit you gave back in the Partial credit box. On a 120-point exam with 14 points marked wrong and 1.5 points of partial credit, the score is (120 − 14 + 1.5) ÷ 120 × 100 = 89.58%. Choose half-point chart steps if you grade in halves.
Can I use my own grading scale?
Yes. Choose Custom and type the lowest percent that earns an A, B, C and D; anything below the D cutoff is an F. The cutoffs must step down from A to D, for example 94, 86, 75 and 65 for a stricter course, and the chart updates as you type.
How do I print a grading chart for my class?
Set the number of questions, the scale and the rounding rule, then press Print chart. Only the chart is printed, with every number wrong, number right, percent and letter, so it can sit next to your answer key. Pick half-point steps first if your tests award half credit.
💡 Good to know
The 10% rule of thumb
On the 10-point scale a student can miss 10% of the questions, rounded down, and keep an A; 20% for a B, 30% for a C and 40% for a D. On a 45-question test that is 4, 9, 13 and 18 misses.
Long tests forgive single misses
One question is worth 4 points on a 25-question quiz but only 1 point on a 100-question exam. Spreading a unit test over more items makes each careless error cost less.
Half-point charts match half-point grading
If you award half credit, switch the chart to half points. A 20-point quiz then lists 41 rows, from 0 to 20 points off in steps of 0.5, so 2.5 points off (87.5%) has its own line.