Final Grade Calculator: What Score Do I Need on the Final?
Updated 30 March 2026
Finals week is stressful enough without guessing what score you need. The formula is straightforward: Required Final Score = (Target Grade - Current Grade x (1 - Final Weight)) / Final Weight. If you have an 85% in the class and the final is worth 30%, you need a 91.7% on the final to get a B+ (87%) overall. This page gives you instant answers for the most common scenarios so you can stop guessing and start studying.
The Formula
Required Score = (Target - Current x (1 - Final Weight)) / Final Weight
Example: Current grade 85%, Final weight 30%, Target B+ (87%). Required = (87 - 85 x 0.70) / 0.30 = (87 - 59.5) / 0.30 = 27.5 / 0.30 = 91.7%
Quick Reference: Required Final Exam Scores
Find your current grade and final exam weight below. Scores marked with * exceed 100% and are not achievable without extra credit.
| Current | Final Weight | For A (93%) | For A- (90%) | For B+ (87%) | For B (83%) |
|---|---|---|---|---|---|
| 95% | 20% | 83.0% | 68.0% | 53.0% | 33.0% |
| 95% | 30% | 88.3% | 78.3% | 68.3% | 55.0% |
| 90% | 20% | 105.0%* | 90.0% | 75.0% | 55.0% |
| 90% | 30% | 100.0% | 90.0% | 80.0% | 66.7% |
| 85% | 20% | 125.0%* | 110.0%* | 95.0% | 75.0% |
| 85% | 30% | 111.7%* | 101.7%* | 91.7% | 78.3% |
| 85% | 40% | 105.0%* | 97.5% | 90.0% | 80.0% |
| 80% | 20% | 145.0%* | 130.0%* | 115.0%* | 95.0% |
| 80% | 30% | 123.3%* | 113.3%* | 103.3%* | 90.0% |
| 80% | 40% | 112.5%* | 105.0%* | 97.5% | 87.5% |
| 75% | 30% | 135.0%* | 125.0%* | 115.0%* | 101.7%* |
| 75% | 40% | 120.0%* | 112.5%* | 105.0%* | 95.0% |
| 70% | 30% | 146.7%* | 136.7%* | 126.7%* | 113.3%* |
| 70% | 40% | 127.5%* | 120.0%* | 112.5%* | 102.5%* |
* Score exceeds 100% and is not achievable without extra credit. Standard grading scale: A = 93%+, A- = 90-92%, B+ = 87-89%, B = 83-86%.
Key Takeaways From the Table
A 95% going into the final gives you huge flexibility
With a 95% current grade and a 30% final, you only need 88.3% on the final to keep an A. You can score as low as 55% on the final and still get a B. This is why consistent performance throughout the semester matters more than the final exam alone.
Below 85%, an A becomes very difficult
Once your current grade drops below 85%, achieving an A (93%) requires a final score above 100% in most scenarios. At 80% current with a 30% final, you would need 123.3% on the final for an A. Even an A- (90%) requires 113.3%. At this point, B+ is the realistic ceiling unless extra credit is available.
Higher final weight gives you more recovery room
A 40% final exam weight is actually advantageous if you are behind. At 80% current with a 40% final, you need 97.5% on the final for a B+. With only a 20% final, the same B+ requires an impossible 115%. The heavier the final, the more your final performance can move the needle.
What to Do When Your Target Is Impossible
If the required score exceeds 100%, you have three options. First, check if your professor offers extra credit opportunities during finals week. Some professors allow bonus questions on the final exam worth 5-10 extra points. Second, ask your professor if they curve final grades. In large lecture courses, curving is common and can shift grade boundaries by 2-5 percentage points. Third, adjust your target. If an A- is impossible but a B+ is achievable with a 92% on the final, focus your study effort on achieving that realistic target rather than stressing about an unreachable one.
One more consideration: some professors allow grade replacement, where a strong final exam score replaces a lower midterm score. If this policy exists in your class (check the syllabus or ask directly), the final has even more power to change your grade than the standard weight suggests. A student who scored 65% on a midterm worth 25% could potentially replace it with a 90% final exam score, gaining 6.25 additional percentage points (25% weight x 25-point improvement).