What grade do I need on my final exam?

The required-final-score formula

Let C be your pre-final grade, T your target overall grade, and w the final exam's weight as a decimal. Your final course grade is C × (1 − w) + exam score × w. Rearranging that equation gives the required exam score.

Required final (%) = [T − C × (1 − w)] ÷ w

Worked example: reach an 85% course grade

Your current grade is 80%, and the final is worth 25%, so w = 0.25. The pre-final contribution is 80 × 0.75 = 60. Subtract that from the target: 85 − 60 = 25. Divide by 0.25 to get a required final score of 100%.

What a result above 100% means

With a current grade of 82%, a target of 90%, and a 25% final weight, the required score is 114%. Without extra credit or other grading adjustments, a final capped at 100% cannot reach that target. A perfect final would produce 86.5% overall. A calculator cannot predict whether your teacher will allow extra credit.

What a result of zero or less means

A nonpositive result means the target is already mathematically secured even with a zero on the final under this weighted-average model. For example, 95% currently, a target of 70%, and a 20% final weight gives −30%. This does not override a course rule requiring you to take or pass the exam.

Check your inputs before planning

Use a current grade that excludes the final. Enter the final's weight in the whole course, not its weight within a tests category. The weight must be greater than 0% and no more than 100%. Course-specific rounding, minimum exam requirements, and multiple remaining exams can change the interpretation.