Final Grade Calculator
Tell us your current course grade, the final exam\u2019s weight, and your target — we will tell you the exact score you need to ace the exam (or, occasionally, to relax).
Find out exactly what score you need on your final exam to hit your target grade in a class.
The math behind the calculator
Your overall course grade is a weighted average of your work-to-date and the final exam. Algebraically:
overall = current × (1 − w) + final × w
where w is the final exam\u2019s weight (expressed as a decimal, so 30% = 0.30). Setting overall to your target and solving for final:
final = (target − current × (1 − w)) / w
If final > 100, your target is mathematically out of reach. If final < 0, you have already secured your target and could legitimately skip the exam (don\u2019t).
Worked example
Suppose your current grade is 82%, the final exam is worth 30%, and your target is a B+ (87%). The math:
final = (87 − 82 × 0.70) / 0.30 = (87 − 57.4) / 0.30 = 29.6 / 0.30 = 98.67%
That is doable but tough. Lowering your target to a B (83%) drops the requirement to a 84.7% — much more comfortable. Use the calculator above to see the trade-off in real time.
Strategy: working backwards from a letter grade
If you are aiming for a specific letter grade, target the lower bound of the band so you have a margin of safety:
- A = 93% (or 90% at schools that do not use plus/minus)
- A- = 90%
- B+ = 87%
- B = 83%
- B- = 80%
Hitting the lower bound by 1–2 points gives you insurance against rounding errors or a missed extra-credit opportunity.
Frequently asked questions
How is the score I need on the final calculated?
We solve the algebra: current grade × (1 − final weight) + final score × final weight = target grade. Rearranged for the unknown final score, that is: final score = (target − current × (1 − weight)) / weight.
What if I need more than 100% to reach my target?
Then your target is mathematically impossible — the calculator will say so. You will need to ask about extra credit, contest a graded assignment, or accept a slightly lower letter grade.
My professor weights the final differently for high vs. low scores. Can the calculator handle that?
Most professors who do this use a "replace the lowest grade" rule. Calculate your needed final twice — once with your current weighted grade, and once assuming the final replaces your lowest exam — and pick the easier path.
Can I work backwards from a target letter grade?
Yes — convert your target letter grade to its lower-bound percentage (B = 83%, A- = 90%, etc.) and use that as your target. Our scale converter shows the cutoffs.