Quick answer
The score you need on the final is (target − current × (1 − weight)) ÷ weight. With an 85 now, a 90 goal and a final worth 20%, you would need 110% — more than a perfect score, so that goal needs extra credit.
Enter your current grade, the grade you want and how much the final exam counts. The calculator solves for the exam score you need and tells you whether it is reachable.
Related tools: Grade Calculator: Percentage grade from points earned and points possible. Grade Curve Calculator: Apply a flat or proportional curve to a set of scores. Weighted Grade Calculator: Course grade from scores and their weights.
How to use the Final Grade Calculator
- Enter current grade (%) (0 or more).
- Enter grade you want (%) (0 or more).
- Enter final exam weight (%) (between 0 and 100).
- Press Calculate to see the result, and use Reset to start again.
| Input | What to enter | Allowed values |
|---|---|---|
| Current grade | A number, in % | ≥ 0 |
| Grade you want | A number, in % | ≥ 0 |
| Final exam weight | A number, in % | > 0, ≤ 100 |
Formula and method
Formula
needed = (target − current × (1 − weight)) ÷ weight
Rounded to 2 decimal places for GPA, 2 for percentages.
A result above 100% means the target is only reachable with extra credit.
Worked examples
These examples are verified: each one is an automated test case that the live calculator must reproduce exactly.
Example 1
Inputs: Current grade = 85; Grade you want = 90; Final exam weight = 20.
| Result | Value |
|---|---|
| Score needed on the final | 110% |
| Reachable | No — needs extra credit |
Example 2
Inputs: Current grade = 80; Grade you want = 85; Final exam weight = 25.
| Result | Value |
|---|---|
| Score needed on the final | 100% |
| Reachable | Yes |
Example 3
Inputs: Current grade = 92; Grade you want = 90; Final exam weight = 20.
| Result | Value |
|---|---|
| Score needed on the final | 82% |
| Reachable | Yes |
The first line is the headline result (score needed on the final). Below it the final Grade Calculator lists reachable, which describe the same case from other angles. Rounded to 2 decimal places for GPA, 2 for percentages.
Why the answer can be above 100
The current grade covers the other 80% of the course. To lift an 85 to a 90 with a final worth only 20%, the exam must pull the average up by 5 points, which takes (90 − 68) ÷ 0.2 = 110. The calculator flags this as not reachable rather than hiding it.
Try a lower target
Dropping the goal to 87 needs (87 − 68) ÷ 0.2 = 95. Small changes in the target move the required score by five times as much when the final is worth 20%, which is the reason a heavy final weight matters so much.
How the result changes with current grade
Holding every other input at the first worked example, this table changes only current grade. It shows how sensitive the answer is to that one value; each row was produced by running this calculator.
| Current grade | Score needed on the final | Reachable |
|---|---|---|
| 42.5 | 280% | No — needs extra credit |
| 85 | 110% | No — needs extra credit |
| 170 | 0% | Yes |
| 340 | 0% | Yes |
What happens with invalid input
These messages are produced by the calculator itself, so you know what to fix.
- Final exam weight: entering "0" shows "Final exam weight must be greater than 0." beside that field and no result.
Choosing between the Final Grade Calculator and similar calculators
Each row shows what a related calculator on this site asks for and what it returns, so you can pick the one that matches your question.
| Calculator | You enter | It returns |
|---|---|---|
| [Grade Calculator](/education/grade-calculator/) | points earned and points possible | Grade |
| [Grade Curve Calculator](/education/grade-curve/) | scores, score the top student should get and curve | Curved scores |
| [Weighted Grade Calculator](/education/weighted-grade-calculator/) | scores and weights | Weighted grade |
| [Class Rank Percentile Calculator](/education/class-rank-percentile-calculator/) | your rank and class size | Percentile |
| [Weighted GPA Calculator](/education/weighted-gpa-calculator/) | grade points per course, credits per course and extra points per course | Weighted GPA |
Assumptions and limitations
- Over 100% flagged as not reachable without extra credit
- Negative result means the target is already secured
If a required value is empty, not a number, or outside its allowed range, the form marks that field with a message and shows no result instead of a misleading number. The automated checks deliberately try invalid entries for final exam weight to confirm this.
Frequently asked questions
What if the final is worth more?
The required score falls. At 40% weight, a 90 goal from an 85 needs (90 − 51) ÷ 0.4 = 97.5.
Does it handle extra credit?
It reports scores above 100 as unreachable without extra credit; it does not know your instructor's extra-credit policy.
What if I want to pass, not get an A?
Set the target to your passing grade. The same formula applies.
What does the Final Grade Calculator calculate?
The score needed on a final exam to reach a target course grade. It returns Score needed on the final and Reachable.
What formula does the Final Grade Calculator use?
needed = (target − current × (1 − weight)) ÷ weight. A result above 100% means the target is only reachable with extra credit.
What do I need to enter in the final Grade Calculator?
You enter Current grade (%), Grade you want (%) and Final exam weight (%).
How is the result rounded or limited?
Rounded to 2 decimal places for GPA, 2 for percentages. Over 100% flagged as not reachable without extra credit.
What are the limits of this calculator?
Over 100% flagged as not reachable without extra credit. Negative result means the target is already secured.
What is an example of a final Grade result?
With current grade 85, grade you want 90 and final exam weight 20, the score needed on the final is 110%.
Related calculators
- Grade Calculator — Percentage grade from points earned and points possible.
- Grade Curve Calculator — Apply a flat or proportional curve to a set of scores.
- Weighted Grade Calculator — Course grade from scores and their weights.
- Class Rank Percentile Calculator — Percentile from class rank and class size.
- Weighted GPA Calculator — GPA with extra points for honors or advanced courses.
- Letter Grade to GPA Calculator — Grade points for a letter grade on the 4.0 scale.
- GPA to Letter Grade Calculator — Nearest letter grade for a GPA on the 4.0 scale.
Sources
- Common US 4.0 unweighted grading convention; institutions may differ, so confirm with your school's registrar
Content last reviewed 2026-11-04. Formulas and worked examples are checked by automated tests against independently computed values.