Last updated October 10, 2026 · Report an error
Before a final exam, it helps to know exactly what score you need to reach the grade you're aiming for — rather than guessing how much to study.
This calculator works backward from your current grade and the final's weight to find the exact score you need.
How it works
Enter your current grade before the final, how much the final is worth as a percentage of your total grade, and the overall grade you want to achieve. The calculator solves the weighted average equation for the score you need on the final.
- Enter current grade (%, before the final).
- Enter final exam weight (% of total grade).
- Enter desired overall grade (%).
- Click Calculate to see your results.
Examples
A reachable target
With an 85% current grade, a final worth 30% of the total, and a goal of 87% overall, you'd need a 91.67% on the final.
An already-secured grade
With a 95% current grade and the final worth only 20%, you could score as low as 70% overall on the final and still finish with at least a 90% overall.
Who should use it
- Figuring out how much a final exam actually matters before deciding how hard to study.
- Setting a realistic grade target based on what's mathematically achievable.
Industry applications
- Student academic planning
- Tutoring and academic advising
Advantages
- Clearly flags when a target grade is already achieved or mathematically out of reach.
- Shows the full weighted-average formula, not just the final answer.
Limitations
- Assumes a simple two-part weighting (current grade vs. final) — doesn't model more complex grading schemes with multiple separately-weighted components.
Common mistakes to avoid
- Using the wrong weight for the final exam — double-check your syllabus rather than guessing.
- Forgetting that "current grade" should reflect your grade on everything except the final, not your grade including any prior exams weighted separately.
Best practices
- Recalculate as soon as you get your current grade confirmed close to the final, since small changes in your current grade can meaningfully shift the score you need.
Tips
- If the needed score feels out of reach, check whether your course allows dropping a low grade or extra credit — those can change your "current grade" input entirely.