Grading Calculator
This page opens the calculator in weighted mode, which is how a syllabus usually describes a course: homework worth 25, quizzes 15, the midterm 25 and the final 35, each with the percentage scored in it. Those four categories are already in the boxes, giving 89.15% and a B+, and every figure follows whatever you change them to. Weights do not have to add up to 100, categories can be added or removed as the term goes on, and the letter is read off a scale you pick rather than one assumed for you.
89.15% (B+) from 89.15 of 100 weight on the plus / minus scale.
One row per category: its share of the grade and the score in it. Press Enter in any field to add another line.
Worked examples
Each one runs through the same code the page above does, on the plus / minus scale, so switching the scale moves them too.
The scale in use
Every band includes its own floor and runs up to the next one, so 89.99% is a B+ and 90% is an A-. Nothing is rounded on the way to a letter.
| Letter | Percentage band |
|---|---|
| A+ | 97% and above |
| A | 93% up to 97% |
| A- | 90% up to 93% |
| B+ | 87% up to 90% |
| B | 83% up to 87% |
| B- | 80% up to 83% |
| C+ | 77% up to 80% |
| C | 73% up to 77% |
| C- | 70% up to 73% |
| D+ | 67% up to 70% |
| D | 63% up to 67% |
| D- | 60% up to 63% |
| F | 0% up to 60% |
Common questions
- How do I calculate a grade from weighted categories?
- Multiply each category percentage by its weight, add those up, and divide by the total weight. With homework at 94% weighing 25, quizzes at 88% weighing 15, a midterm at 81% weighing 25 and a final at 92% weighing 35, that is 2350 + 1320 + 2025 + 3220 = 8915, divided by the total weight of 100, which is 89.15%. The Contributes column beside each row shows the weighted points that category adds, 23.5 for the homework above, so the arithmetic can be followed line by line.
- What if my weights do not add up to 100?
- They are normalised by their own total, and the line under the result says so. A course that has only graded homework worth 30 and an exam worth 60 gives 83.33%, with a note that the weights add up to 90, not 100, and that each is scaled by 100 ÷ 90. That is the right answer for a term in progress: it averages what has actually been graded rather than treating the ungraded 10 as a zero.
- Can I add a category part way through the term?
- Yes. Add category puts a new line at the bottom, and pressing Enter in any of a line's fields does the same thing. Remove takes a line out. A line left completely blank is skipped rather than counted as a zero, so a category you have not scored yet cannot quietly drag the average down.
- Can I grade by points instead of by weights?
- Switch the Mode control to Points and enter each assignment as points earned over points possible. That is a different number from the weighted one, and the difference is real: a 10-point quiz at 100% with a 200-point exam at 80% is 80.95% by points and 90.00% weighted at half each. Use whichever one your syllabus describes.
- Does this page keep or send what I enter?
- Nothing is sent. The arithmetic happens in the page itself, and the categories, weights and scale are kept only in this browser's own storage so the page is still filled in next time. There is no account, no upload and no server involved in producing the number.
Exact arithmetic on the points you enter, against the scale you choose. It cannot know your school's rounding rule, a dropped lowest score or extra credit, so set the scale and check the syllabus before you read the letter.