📝 Weighted Grade Calculator
By ToolNimba Editorial Team · Updated 2026-06-20
This weighted grade calculator turns a list of assignment scores and their weights into a single overall grade for your class. Add a row for each component, such as homework, quizzes, a midterm and a final, then enter the grade and the weight for each one. The tool instantly shows your weighted grade, an equivalent letter, and a clear check on whether your weights add up to 100%.
What is the Weighted Grade Calculator?
A weighted grade reflects the fact that not every assignment counts equally toward your final mark. A daily homework set might be worth 10% of the grade while the final exam is worth 40%. To combine them fairly you cannot just average the percentages, because that would treat a five minute quiz the same as a three hour exam. Instead you multiply each grade by its weight, add those products together, and divide by the total weight. That division by the total weight is what keeps the result on a 0 to 100 scale even when your weights do not add up perfectly.
The core formula is final grade = sum of (grade times weight) divided by sum of (weight). Suppose homework is 88% at a weight of 20, a midterm is 76% at a weight of 30, and a final is 91% at a weight of 50. The numerator is (88 x 20) + (76 x 30) + (91 x 50), which is 1760 + 2280 + 4550 = 8590. The denominator is 20 + 30 + 50 = 100. Dividing gives 85.9%, your weighted grade. Because the weights happen to sum to 100 here, the division by 100 is the same as treating each weight as a percentage of the whole.
Many syllabuses list weights that are meant to total 100%, but in practice students often enter only the categories they have grades for so far, or they mistype a number. This calculator does not force the weights to total 100. It always divides by whatever total weight you enter, so the answer stays mathematically valid, and it separately tells you how far your weights are from 100% so you can spot a missing or mistyped category. This is also exactly how you project a grade mid semester: enter only the work that has been graded, read the weighted average of what you have, and treat any leftover weight as still to come.
The letter grade shown next to your percentage uses a common United States scale where 93 and above is an A, 90 to 92 is an A minus, 80 to 82 is a B minus, and so on down to an F below 60. Grading scales vary widely between schools, instructors and countries, so treat the letter as a quick reference rather than an official conversion. The percentage is the precise, portable number to record, and you can copy it to your clipboard with one click.
When to use it
- Working out your current overall grade in a class from a syllabus that splits the mark into weighted categories like homework, quizzes, projects and exams.
- Projecting where you stand mid semester by entering only the assignments that have been graded so far and reading the weighted average of completed work.
- Checking a grade your instructor reported by reconstructing it from the individual component scores and their published weights.
- Deciding which upcoming assignment matters most by seeing how a heavily weighted final moves your overall grade compared with a lightly weighted quiz.
How to use the Weighted Grade Calculator
- Enter a name, the grade as a percentage, and the weight for your first assignment in the first row.
- Click Add assignment to create another row, and repeat for every graded component of the class.
- Read the weighted grade and the equivalent letter in the result panel, which updates as you type.
- Check the total weight note to confirm your weights add up to 100%, then copy the result if you need it.
Formula & method
Worked examples
Your class is graded as homework 88% at weight 20, a midterm 76% at weight 30, and a final exam 91% at weight 50. The weights add up to 100.
- Multiply each grade by its weight: 88 x 20 = 1760, 76 x 30 = 2280, 91 x 50 = 4550.
- Add the products: 1760 + 2280 + 4550 = 8590.
- Add the weights: 20 + 30 + 50 = 100.
- Divide the total products by the total weight: 8590 / 100 = 85.9.
Result: Your weighted grade is 85.9%, which is a B on a typical scale.
It is mid semester and only two categories are graded so far: a quiz at 70% with weight 25 and a project at 95% with weight 75. You want the weighted average of completed work.
- Multiply each grade by its weight: 70 x 25 = 1750, 95 x 75 = 7125.
- Add the products: 1750 + 7125 = 8875.
- Add the weights of the graded work: 25 + 75 = 100.
- Divide: 8875 / 100 = 88.75.
Result: The weighted average of your graded work is 88.75%, an A minus, with the rest of the course still to come.
Common grade weighting schemes for a single class
| Component | Typical weight | Notes |
|---|---|---|
| Homework / participation | 10% to 20% | Many small assignments, low individual stakes. |
| Quizzes | 10% to 20% | Frequent checks on recent material. |
| Projects / labs | 15% to 30% | Larger graded work spread across the term. |
| Midterm exam | 20% to 30% | Covers the first half of the course. |
| Final exam | 25% to 40% | Often the single heaviest component. |
Percentage to letter grade on a common US scale
| Percentage | Letter |
|---|---|
| 97 to 100 | A+ |
| 93 to 96 | A |
| 90 to 92 | A- |
| 87 to 89 | B+ |
| 83 to 86 | B |
| 80 to 82 | B- |
| 77 to 79 | C+ |
| 73 to 76 | C |
| 70 to 72 | C- |
| 67 to 69 | D+ |
| 63 to 66 | D |
| 60 to 62 | D- |
| Below 60 | F |
Common mistakes to avoid
- Averaging the grades instead of weighting them. Taking a plain average of your percentages ignores how much each assignment counts. A 60% on a final worth 40% hurts far more than a 60% on a quiz worth 5%, and only the weighted method captures that difference.
- Assuming weights must total exactly 100. The math works for any positive total weight because the formula divides by the sum of the weights. If your weights total 90 or 110 the answer is still valid, but it usually means you left out a category or mistyped one, so check the total weight note.
- Entering weights as decimals and grades as percentages. Keep both columns in the same style. If you enter a weight of 0.2 instead of 20 the row will still compute, but mixing 0.2 with another row of 30 throws the proportions off. Use whole percentages for every weight.
- Forgetting ungraded work when projecting a grade. If you only enter the assignments graded so far, the result is the average of completed work, not your guaranteed final grade. The remaining weighted assignments can still move it up or down.
Glossary
- Weighted grade
- An overall grade that combines several scores after multiplying each by how much it counts, then dividing by the total weight.
- Weight
- A number, usually a percentage, that says how much a single assignment or category contributes to the final grade.
- Component
- One graded part of a class, such as homework, a quiz, a project, a midterm or a final exam.
- Weighted average
- The general statistical method behind this tool: a mean where each value is scaled by its weight before averaging.
- Letter grade
- A letter such as A, B or C mapped from a percentage range. The exact cutoffs depend on the school or instructor.
- Total weight
- The sum of all the weights you enter. The calculator divides by this number, and ideally it equals 100 for a full grade.
Frequently asked questions
How do I calculate a weighted grade?
Multiply each assignment grade by its weight, add those products together, then divide by the sum of the weights. For example (88 x 20 + 76 x 30 + 91 x 50) / 100 = 85.9%. This calculator does every step for you as you type.
Do my weights have to add up to 100%?
No. The formula divides by whatever your weights total, so the result is correct for any positive total. The tool still tells you how far your weights are from 100% because a total that is off usually signals a missing or mistyped category.
What is the difference between a weighted grade and a simple average?
A simple average treats every score equally. A weighted grade scales each score by how much it counts, so a heavily weighted final exam moves your grade much more than a lightly weighted quiz. Use weighting whenever your syllabus assigns different percentages to categories.
Can I use this to project my final grade before the course ends?
Yes. Enter only the assignments that have been graded so far and read the weighted average of completed work. Any leftover weight represents work still to come, which can raise or lower your final grade.
How do I add or remove assignments?
Click Add assignment to create a new row, and use the Remove button on any row to delete it. The weighted grade and the total weight recalculate instantly each time you change a row.
Is the letter grade official for my school?
Not necessarily. The letter uses a common US scale where 93 and above is an A. Cutoffs vary by school, instructor and country, so treat the letter as a quick guide and record the precise percentage for anything official.