Education · 1 min read
How to calculate your final grade
Your course grade is a weighted average. Knowing the weight of the final exam lets you solve for the score you need.
Last updated November 5, 2026
The formula
Needed final score
needed score = (target grade − current grade × (1 − final weight)) ÷ final weight
- target grade
- the course grade you want, in percent
- current grade
- your grade in everything except the final, in percent
- final weight
- the final's share of the course as a decimal, for example 0.30 for 30%
Worked example
Worked example
85% now, final worth 30%, target 90%
| Step | Calculation | Value |
|---|---|---|
| Weight of the rest | 1 − 0.30 | 0.70 |
| Points from the rest | 85 × 0.70 | 59.5 |
| Points needed from the final | 90 − 59.5 | 30.5 |
Result: 30.5 ÷ 0.30 = 101.7% needed on the final
A score above 100% means the target is out of reach unless your instructor offers extra credit.
Try other targets
Worked example
Same course, different targets
| Target | Calculation | Needed on the final |
|---|---|---|
| 90% | (90 − 59.5) ÷ 0.30 | 101.7% |
| 85% | (85 − 59.5) ÷ 0.30 | 85% |
| 80% | (80 − 59.5) ÷ 0.30 | 68.3% |
Things to check
Important
- Use the weights from your syllabus. Some courses drop the lowest score or curve the final.
- If your current grade includes the final's weight already, remove it first or use a weighted grade calculator.
- Round up: a needed 84.2% means aim for at least 85% to be safe.