Grade Calculator
Find out what score you need on a final exam to reach your desired overall grade.
About the Grade Calculator
Before a final exam, students often want to know exactly what score is needed to reach a target overall grade — this calculator works backward from your current grade, its weight, the final's weight, and your desired final grade to tell you the required final exam score.
How It Works
The calculator treats your overall desired grade as the weighted sum of your current grade's contribution and the final exam's unknown contribution, then solves algebraically for the final exam score needed to make that sum equal your desired grade.
Required Final Score (%) = (Desired Grade − Current Grade × Current Weight) / Final Weight, with weights expressed as decimals.
Worked example
Scenario: A current grade of 82% worth 70% of the course, a final exam worth 30%, and a goal of 90%.
- Points already earned: 82 × 0.70 = 57.4.
- Points still needed: 90 − 57.4 = 32.6.
- Required final score: 32.6 ÷ 0.30 = 108.67%.
Result: 108.67% on the final — the 90% goal isn't reachable without extra credit.
Tips and common mistakes
- Current weight plus final weight should add up to 100%; if they don't, the calculator explains its assumption.
- To see what's achievable, lower the goal: 85% needs 92%, and 80% needs 75.33%.
- If the required score is zero or below, the goal is already secured.
Assumptions & Limitations
- Assumes the current grade and weight accurately reflect everything completed so far, and the final exam is the only remaining graded component.
- Weights for current work and the final exam should add up to 100% of the total course grade.
- If other assignments remain besides the final exam, they need to be factored into a revised 'current grade and weight' figure first.
Weighted grades need weighted math
If assignments or categories have different weights, a simple average can give the wrong result. Multiply each score by its weight and add the weighted contributions. Make sure the weights included in the calculation represent the grading scheme you intend to measure.
Example: an 80% exam worth 60% and a 90% project worth 40% produce 84% overall: (80 × 0.60) + (90 × 0.40).