Find out exactly what you need on the final exam to reach your target grade, and what happens if you ace it or skip it.
The formula
Needed = (Target − Current × (1 − w)) ÷ w
Here w is the final's weight as a decimal. With a current grade of 86%, a target of 90% and a final worth 20%: (90 − 86 × 0.8) ÷ 0.2 = (90 − 68.8) ÷ 0.2 = 106%. That's out of reach without extra credit, and you would need 56% on the final to finish with at least 80%.
Tips
- Use your grade without the final included, which is what most online gradebooks show before the exam.
- If the needed score is above 100%, look at the table for the best grade you can still get.
- Bigger finals swing grades more: a final worth 40% can move you a whole letter grade either way.
How we checked this
Before every update, this calculator is run in a real browser with these known answers, and it must match all of them:
- 86% now, final worth 20%, want 90%: need 106% ✓
- To keep 80%: need 56% ✓
Last checked October 26, 2026. Spotted something wrong? The math is done in your browser with the formula shown on this page, so you can check any result by hand.
Questions people ask
What do I need on my final to get an A?
Enter your current grade, 90 as the grade you want, and the final's weight. The calculator shows the exact score, and the table shows the scores for A, B, C and D.
What if I get a 0 on the final?
Your grade becomes current grade × (1 − the final's weight). With 86% and a final worth 20%, that's 68.8%.
Can I still pass?
Look at the D (60%) row. If it says 'Already safe', you'll pass even with a zero on the final.