Combines several weighted grade categories — homework, quizzes, a final exam — into one overall course grade.
How it works
Each category’s score is multiplied by its weight, the products are summed, and the total is divided by the sum of the weights.
What this does not include
This does not include solving for an unknown score — for “what do I need on my final,” use this site’s final grade calculator instead. This tool computes a current grade from already-known scores.
How to use this calculator
- Enter each category’s score and weight.
A worked example
Homework: 85%, weighted 20%. Quizzes: 78%, weighted 30%. Final exam: 90%, weighted 50%.
Weighted sum = (85 × 0.20) + (78 × 0.30) + (90 × 0.50) = 17 + 23.4 + 45 = 85.4% overall.
What the variables mean
| Variable | Meaning |
|---|---|
| Category score | The percentage earned in that category |
| Category weight | How much that category counts toward the final grade |
Edge cases worth knowing
Weights don’t need to sum to exactly 100. The calculator divides by the total weight entered, so 20 + 30 + 45 (summing to 95, not 100) still produces a correct proportional result.
A category weighted at zero has no effect on the total, regardless of the score entered for it — useful for a category marked “does not count this term.”
Frequently asked questions
Why not just average all the category scores directly?
A plain average treats a 50%-weighted final exam the same as a 5%-weighted homework category — weighting by importance gives the correct overall picture when categories carry different weights.
What happens if all weights are equal?
The weighted average reduces to the same result as a plain unweighted average, since every category counts equally either way.
Do the weights need to add up to 100%?
No — the calculator normalizes by the total weight entered, so it works correctly even if the weights don’t sum to exactly 100.
