What Grade Do I Need on the Final Exam?

The formula

Needed final score = (target - current x (1 - w)) / w, where w is the final's weight as a decimal. In plain terms: subtract the grade your existing work already locks in, then scale up by how much the final counts.

A worked example

Suppose your current grade is 82%, you want an 80% overall, and the final is worth 30% (so w = 0.30). Needed = (80 - 82 x 0.70) / 0.30 = (80 - 57.4) / 0.30 = 22.6 / 0.30 = about 75%. So a 75% on the final keeps your 80%. The Final Grade Calculator does this for any target and weight.

When the number is impossible

Sometimes the formula returns more than 100% — meaning the target is out of reach on the final alone — or a negative number, meaning you have already secured it and could score zero and still pass. Both are useful: one tells you to adjust the target, the other tells you where you can ease off.

Frequently asked questions

What if I do not know the final's weight? Check the syllabus — the weighting is the one number this calculation cannot do without.

Does rounding matter? At the edge, yes — if you need 89.6% for an A-, confirm how your school rounds before assuming you are safe.

Can I plug in a stretch goal? Absolutely — try a few targets to see which are realistic and which would need a near-perfect final.