Grading Calculator
The grading calculator turns the questions on a test and the number wrong into a percent and a letter grade, with an easy grader chart for every possible score.
Grade
- Percent 22 of 25 right: 22 / 25 x 100 = 88%.
- 88%
- Letter grade On the 10-point scale, B is 80% up to 90%.
- B
- Wrong and right
- 3 wrong, 22 right
- Under each rounding rule
- exact 88% B, rounded 88% B, truncated 88% B
- Scale used
- A 90+, B 80+, C 70+, D 60+, F below 60
| Wrong | Right | Percent | Grade |
|---|---|---|---|
| 0 | 25 | 100% | A |
| 1 | 24 | 96% | A |
| 2 | 23 | 92% | A |
| 3 (entered) | 22 | 88% | B |
| 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 |
How the Grading Calculator works
A grading calculator turns a raw score into a percent and a letter. Divide the number right by the number of questions and multiply by 100. On a 25-question quiz with 3 wrong, that is 22 / 25 x 100 = 88%, a B on the 10-point scale.
A teacher with a stack of the same test does not want to divide thirty times. An easy grader calculator does the division once for every possible score: 0 wrong, 1 wrong, 2 wrong and so on down to the last question, each with its percent and letter. Mark the papers, count the misses and read the grade off the chart. On a 25-question test each miss costs 4 percent; on a 40-question test each costs 2.5 percent.
When questions carry different weights, grade in points. As a points grading system calculator, the total is the test's total points and the number wrong is the points missed, and the division is the same. If every question is worth the same, say 4 points, the percent does not change, since equal points cancel. Partial credit works as a fraction: half a question wrong is 0.5.
The 10-point scale gives an A from 90%, a B from 80%, a C from 70% and a D from 60%, with F below. The calculator starts on the 10-point grading scale. The 7-point scale is stricter: A from 93%, B from 85%, C from 77% and D from 70%, so a 92% is a B and a 69% fails. The plus/minus version splits each 10-point band into thirds: A- at 90, A at 93 and A+ at 97, down to D- at 60. All three are common conventions and none is any school's official policy; schools, districts and teachers set their own cutoffs, such as A 92, B 83, C 74, D 65.
Rounding decides borderline grades. On a 48-question test with 5 wrong, the score is 43 / 48 = 89.58%. Kept exact, that is a B. Rounded half up to a whole percent it is 90%, an A. Truncated it is 89%, a B again. On the 7-point scale, 25 of 27 is 92.59%: a B exact, an A rounded. Teachers and gradebook software make different choices here.
Grading Calculator FAQ
How do you calculate a test grade percentage?
Divide the number right by the total and multiply by 100. 22 right out of 25 is 22 / 25 x 100 = 88%. With points it is the same: 85 points out of 95 is 89.47%.
What grade is 3 wrong out of 25?
88%. That is a B on the 10-point scale and on the 7-point scale, and a B+ on the plus/minus scale, where B+ runs from 87% up to 90%. Each wrong answer on a 25-question test costs 4 percent.
What is the 10-point grading scale?
A is 90% and above, B is 80% up to 90%, C is 70% up to 80%, D is 60% up to 70%, and F is below 60%. The plus/minus version adds a minus at the bottom of each band and a plus at the top: 80% to 82% is a B-, 83% to 86% a B and 87% to 89% a B+.
Is 89.5% an A?
It depends on the rounding rule. Rounded half up to a whole percent, 89.5% becomes 90%, an A on the 10-point scale. Kept exact or truncated, it stays under 90% and is a B. 179 out of 200 is exactly 89.5%, so the school's or gradebook's rounding rule decides.
How do I make an easy grader chart for my test?
List every number wrong from 0 to the number of questions, with the percent and letter for each. On a 25-question test each row is 4 percent below the one before it: 100%, 96%, 92%, 88% and so on. For tests over 100 questions the grading calculator shows the 51 rows around the score being graded.
How do I grade a test where questions are worth different points?
Grade in points: divide the points earned by the test's total points and multiply by 100. A 60-point test with 7 points lost is 53 / 60 = 88.33%.