How to calculate a weighted grade
Most syllabi give each category a weight, such as exams 50% and homework 20%. Your grade is then a weighted average, not a plain average. Here is the method with a full example, including how to read your grade when some work has not been graded yet.
The short version
- Find your average in each category. Add the scores in a category and divide, or use the percentage you were given.
- Multiply each average by its weight. A 92% average in a category worth 20% gives 92 × 20 = 1,840.
- Add the results. Add the products from all graded categories.
- Divide by the total weight graded so far. If all categories are graded the total is 100. Mid-term it is less, which gives your grade on the work graded so far.
Skip the arithmetic. The free Grade Calculator does this for you, shows the formula and the working with your own numbers, and runs in your browser - nothing you type is uploaded. Also useful: Final Grade Calculator, Easy Grader.
The formula
Dividing by the weights you have used, rather than always by 100, is what makes the result correct before the course is finished.
A syllabus example
A syllabus says: homework 20%, quizzes 15%, midterm 25%, project 10%, final exam 30%. Before the final, a student has these averages:
| Category | Score | Weight | Score × weight |
|---|---|---|---|
| Homework | 92% | 20 | 1,840 |
| Quizzes | 85% | 15 | 1,275 |
| Midterm | 78% | 25 | 1,950 |
| Project | 95% | 10 | 950 |
| Total | 70 | 6,015 |
Dividing by 100 instead of 70 would give 60.15% - the mistake that makes students think they are failing when they are not. The final's 30% has not been graded, so it is left out of both the top and the bottom.
Unweighted (total points) grading
Some courses simply add points: your grade is points earned ÷ points possible. A 100-point exam then counts ten times as much as a 10-point quiz automatically. Example: 18 of 20, 45 of 50 and 7 of 10 is 70 ÷ 80 = 87.5%.
Averaging inside a category
If homework has five assignments, first find the homework percentage. Either average the percentages (if each assignment counts equally) or add the points and divide by the total points (if your syllabus says larger assignments count more). Your syllabus decides which, so read how the category is defined.
Dropped scores and extra credit
Remove a dropped lowest score from both the points earned and the points possible before you divide. Extra credit usually adds to the points earned only, which can push a category above 100%. Check whether your instructor caps it.
What to do next
Once you know your current grade, the next question is usually what you need on the final to reach a target. That is a one-line calculation covered in the guide on the final exam score.