How this calculator works
A weighted grade multiplies each category score by its weight, adds them up and divides by the total weight. The final-exam score you need is what makes the weighted average of your current grade and the final equal your target.
Current grade = Σ(score × weight) ÷ Σ weight
Needed on final = (Target − Current × (1 − Final weight)) ÷ Final weight
Assumptions and tips
- Letter grades use the common US scale (93+ A, 90 A−, 87 B+ …). Your school’s cutoffs may differ.
Worked example
Using the default values in the calculator above:
| Input | Value |
|---|---|
| Final exam weight | 25 % |
| Grade you want | 85 % |
| Result | Value |
|---|---|
| Current grade | 85.13 % |
| Letter grade | B |
| Weights entered | 75 % |
| Needed on the final for 85% | 84.6 % |
| Final grade if you score 100% | 88.85 % |
| Final grade if you score 0% | 63.85 % |
Categories:
- Homework: 92% × 20%
- Quizzes: 85% × 15%
- Midterm: 78% × 25%
- Project: 88% × 15%
Step by step:
- Multiply each category score by its weight
- Add the results and divide by the total weight = current grade
- Needed on the final = (target − current × (1 − 25%)) ÷ 25%
Common mistakes to avoid
- Averaging category scores without weights.
- Forgetting that weights should total 100% including the final.
Frequently asked questions
What do I need on my final to get an 85?
With the example categories (current grade 85.1%) and a 25% final, you need about 84.6% on the final.
How do weighted grades work?
Each category counts in proportion to its weight. A 25% midterm counts five times as much as a 5% quiz.