Divide the number right by the total and multiply by 100. 17 out of 20 is 17 ÷ 20 × 100 = 85%, a B on the 10-point scale. Each question on a 20-question test is worth 5%, so every wrong answer takes 5 points off.
How to use it
- Enter the total: the number of questions, or the points the test is out of.
- Enter the score as the number right, or switch to Number wrong if you mark the mistakes. Points work the same way.
- Pick your scale and the rounding your school uses.
- Grade the stack from the chart. Find the number wrong on each paper in the first column. Print the chart to keep it with the answer key.
Which grading scale?
Schools set their own cutoffs, so check your district’s policy. The calculator has three options:
- 10-point: A from 90%, B from 80%, C from 70%, D from 60%, F below. Florida law sets this scale for public school grades 6 to 12 (Florida Statutes §1003.437), and it’s the calculator’s default.
- Plus and minus: the same bands split into thirds, such as B− 80–82, B 83–86 and B+ 87–89. It’s one common way to do it; your school may split them differently.
- Your own: type the lowest percentage for an A, B, C and D. Use it for a 7-point scale or any other.
Scales vary even between official sources. The College Board’s GPA chart, for example, puts a D at 66–69 and an F below 65 (BigFuture).
Rounding: is 89.5% an A?
With Whole number rounding, 89.5% shows as 90% and earns the A. Some gradebooks round this way and some don’t. If your school doesn’t round up, choose One decimal: 89.5% stays 89.5% and is a B. The letter always follows the percentage as shown, so what students see matches the grade.
Common scores
| Score | Percent | 10-point grade |
|---|---|---|
| 8 out of 10 | 80% | B |
| 12 out of 15 | 80% | B |
| 16 out of 20 | 80% | B |
| 17 out of 20 | 85% | B |
| 18 out of 20 | 90% | A |
| 22 out of 25 | 88% | B |
| 23 out of 30 | 76.7% (77%) | C |
| 45 out of 50 | 90% | A |
Full grading scales for common test lengths: 10, 15, 20, 25, 30 and 50 questions.