Final Exam Grade Needed Calculator
Written by Thierno Sadou Diallo, formula verified per our methodology • Last checked on 9/10/2026
The grade needed on a final exam is calculated from the current average, the exam's weight in the final grade, and the target. With a current average of 12/20, a final exam weighing 40%, and a target of 14/20, you need to score 17/20 on the exam.
Explanation
This calculator answers a common end-of-semester question: what grade do you need on the final exam to reach a target average? It assumes the final average is a weighted average between the average already earned (on the rest of the year or continuous assessment) and the final exam grade, each counting for a given percentage of the total. Knowing the average already earned, the weight of the final exam in the overall grade, and the target, this calculator solves the equation to find the missing exam grade. If the result exceeds 20/20, the target is no longer mathematically reachable with this grading system, even with a perfect exam score — a useful signal to adjust expectations or focus on another realistic goal. For a weighted average in another context, see our percentage calculator. (This example uses France's /20 grading scale.)
Example: current average 12/20, exam at 40%, target 14/20
Inputs
Current average: 12/20. Final exam weight: 40%. Target: 14/20.
Calculation
Grade needed = (14 − 12 × (1 − 0.40)) ÷ 0.40 = (14 − 12 × 0.60) ÷ 0.40 = (14 − 7.2) ÷ 0.40 = 6.8 ÷ 0.40 = 17.
Result
You need to score 17/20 on the final exam to reach an average of 14/20.
Frequently asked questions
What does a result above 20/20 mean?
It means the target is no longer reachable, even with a perfect final exam score, given the average already earned and the exam's weight in the overall grade. In that case, it may be more realistic to recalculate with a slightly lower target average, to find the grade actually needed.
How do you find the weight of the final exam in your average?
This percentage is usually specified in the course assessment rules or communicated by the instructor at the start of the year or semester. Failing that, a common system gives 40 to 50% to the final exam and the rest to continuous assessment, but this varies widely by institution and subject.
Does this calculation work if my grading system counts several exams?
This calculator assumes a two-component average: an average already earned and a single final exam remaining, with their respective weights. If several distinct assessments remain, you must first combine them into a single equivalent weighted grade before using this calculator, or handle the calculation in several steps.