Grade Calculator
Before the final exam the question is always the same: what score do I need? Give this calculator your current grade, how much the final is worth and the grade you want, and it works out the exact score required. It also shows what you would need for an A, B, C or D, and tells you when a target is out of reach.
How to use the grade calculator
- Enter your current grade for the part of the course completed so far.
- Enter the percentage of the total grade the final exam is worth.
- Enter your target and read the score needed, then compare with the A to D rows.
Formula
Needed = (target − current × (1 − weight)) ÷ weight, with the weight as a decimal. It comes from: target = current × (1 − weight) + final × weight.
Worked examples
Aiming for an 85
With an 82 going in and a final worth 30%, you need (85 − 82 × 0.7) ÷ 0.3 = 92% on the final.
When it is out of reach
At 60 going in with a 20% final, an A (90) would need 112.5%, so it is not possible without extra credit.
Planning your final exam
The maths behind it
Your course grade is a weighted average: the graded work counts for (1 − w) of the total and the final for w. Setting that equal to your target and solving for the final score gives the formula this tool uses.
Sample scenarios
| Current | Final weight | Target | Needed on final |
|---|---|---|---|
| 82% | 30% | 85% | 92% |
| 82% | 30% | 80% | 75.3% |
| 82% | 30% | 70% | 42% |
The bigger the final’s weight, the more it can change
If the final is worth 50%, a great result can move your grade up by many points, and a poor one can drag it down just as much. When the final is worth only 10%, your current grade already decides most of the outcome.
What to do with the number
Use the required score to decide how to spend study time. If the number is high, prioritise the topics worth the most marks. If it is low, protect your grade by staying consistent rather than cramming.
Practice problems
Try these yourself first, then check your answer. The answers come from the calculator above.
- You have 78% and the final is worth 40%. What do you need for an 80%?
Show answer
Score needed on the final for 80%: 83%
- You have 90% and the final is worth 25%. What do you need for a 92%?
Show answer
Score needed on the final for 92%: 98%
Common mistakes to avoid
- Entering the final’s weight as a decimal (0.3) when the tool expects a percentage (30).
- Using your overall grade so far that already includes the final’s share.
- Ignoring rounding rules or curves that your instructor applies.
Frequently asked questions
How do I calculate the grade I need on my final?
Subtract your current contribution from your target, then divide by the final’s weight. This tool does it for you.
What if the result is over 100%?
That target cannot be reached with the final alone. Ask about extra credit or aim for a lower grade.
What if the result is negative?
You have already secured the target, even with a zero on the final.
How do I work out a weighted grade?
Use the average calculator with the weights option.
Reviewed September 26, 2026 by the SolveCalcPro editorial team. Found a mistake? Tell us; see our editorial policy.