What Do I Need on My Final? How to Calculate It
The exact formula for working out what score you need on a final exam to hit a target course grade, with a worked example and what to do if the target isn't reachable.
"What do I need on my final to get an A?" is a backward version of the weighted grade formula — instead of solving for the overall grade, you already know the target and need to solve for the one missing score.
The formula
Needed score = (target grade × total weight − sum of every other category's weight × score) ÷ the final's weight.
Worked example
Coursework so far is worth 70% of the grade at an 85% average, and the final exam is worth the remaining 30%. Target overall grade: 90%. Needed score: (90 × 100 − 70 × 85) ÷ 30 = (9,000 − 5,950) ÷ 30 = 3,050 ÷ 30 = 101.7% — which is above 100%, meaning a 90% overall isn't reachable even with a perfect final score at this weighting.
What to do if the number comes back too high
- Double check the weights match your actual syllabus — a small weighting error changes the needed score significantly.
- Lower the target to the highest grade that's actually mathematically reachable.
- If it's genuinely out of reach, that's still useful to know early rather than finding out after the final.
The Grade Calculator runs this exact calculation — enter your categories and a target grade and it solves for the score you need, flagging targets that aren't mathematically possible.