Final Grade Calculator
See exactly what score you need on your final exam to hit your target grade — plus a quick table for A, B, and C.
Enter your current grade, desired grade, and the final exam's weight.
Score needed for common targets
| Target grade | Score needed on final | Status |
|---|
Based on common letter-grade cutoffs (A ≥ 90%, B ≥ 80%, C ≥ 70%) — check your syllabus for your school's exact scale.
Some values were far outside a normal grading range and were capped for this calculation.
This is a simple weighted-average estimate — always check your course syllabus for your instructor's exact grading policy (drops, curves, extra credit, etc.).
Every calculation runs in your browser — nothing is sent to a server.
Working backward from the grade you want
Most grade calculators go forward: plug in a set of scores and get an average out. This one runs the arithmetic in reverse. You already know two things — where your grade sits right now, and where you need it to land after the final exam is graded — and the missing piece is the one number you can still control: your final exam score. That's a fundamentally different question from "what's my average," and it's the one students actually ask the night before a final, when every other grade in the course is already locked in.
This matters because a single-percentage average hides how much leverage the final actually has. A final worth 10% of the course can barely move a struggling grade; a final worth 50% can rescue it completely or sink it just as fast. Solving directly for the required score turns that vague anxiety ("do I need to cram?") into a concrete number you can compare against your own realistic ceiling.
Reading the three inputs correctly
- Current grade in the class is your grade before the final is factored in — the number from your school's gradebook or portal right now, not just an average of quiz scores if other categories (homework, labs, participation) already feed into it.
- Desired final grade is the overall course percentage you want after the final is added in, not the score on the final itself.
- Final exam weight is the share of the total course grade the final controls, as a percentage. If your syllabus states it in points instead — say, "the final is worth 200 of 1,000 total points" — convert first: 200 ÷ 1,000 = 20%.
The reverse-engineering formula
A course grade after the final is just a weighted blend of two pieces: everything before the final, and the final itself.
Final course grade = (current grade × non-final share) + (final score × final weight), where non-final share = 1 − final weight.
Isolating the unknown gives the score this calculator reports:
final score needed = (target grade − current grade × non-final share) ÷ final weight
Three outcomes fall out of that one equation, and the calculator labels each of them:
- Achievable — the required score lands between 0% and 100%. It's within reach, though it may still be a stretch.
- Not achievable — the required score comes out above 100%. No exam score can produce that outcome under the current weighting, since nothing scores higher than a perfect paper.
- Already secured — the required score is 0% or lower. Your target is locked in even with a blank final.
Worked examples
Non-final share = 60%. Required score = (80 − 74×0.6) ÷ 0.4 = (80 − 44.4) ÷ 0.4 = 89% on the final.
Required score = (85 − 60×0.8) ÷ 0.2 = (85 − 48) ÷ 0.2 = 185%. Since a final can't exceed 100%, this target is out of reach under the current syllabus weighting — the only paths forward are extra credit, a dropped grade, or a curve.
Required score = (70 − 93×0.85) ÷ 0.15 = (70 − 79.05) ÷ 0.15 = −60.3%. A negative result means the target is locked in regardless of final exam performance.
How the required score shifts with your target
Holding current grade and final weight fixed shows how sensitive the required score is to what you're aiming for. Example below uses a current grade of 82% and a final weight of 30%:
| Target grade | Score needed on final | Achievable? |
|---|---|---|
| 60% | 8.7% | Yes — secured well above this |
| 70% | 42.0% | Yes |
| 80% | 75.3% | Yes |
| 85% | 92.0% | Yes, but tight |
| 90% | 108.7% | No — exceeds 100% |
Notice how the required score accelerates as the target climbs — each extra point of target grade costs more than a point on the final, because the final only counts for 30% of the total. The lower the final's weight, the steeper that curve gets.
Common mistakes
- Entering a raw exam average instead of the current course grade. If homework, labs, or participation already count toward your grade, use the blended percentage from your gradebook, not just your test average.
- Mixing up points and percentages for the weight. "The final is 25 questions" tells you nothing about weight — you need its share of total course points.
- Ignoring a syllabus curve or drop policy. This calculator assumes a straight weighted average; if your instructor drops the lowest quiz or curves the final, your real required score may differ from the raw math.
- Treating "not achievable" as final. It means not achievable under a plain average — extra credit, curves, or a professor's discretion can still change the outcome, so it's worth asking before assuming the grade is set in stone.
What this tool doesn't cover
It handles exactly one remaining assessment. If you still have a final project and a final exam left, or multiple remaining quizzes with different weights, you'll need to combine those into a single effective "remaining weight" and "remaining target" first, or work through the weighted average manually for each piece. This tool also doesn't convert results into a letter grade or GPA — check your institution's own grading scale for that conversion.
Sources & further reading
Frequently asked questions
How do I calculate what score I need on my final exam?
This calculator uses the standard weighted-average grading formula: desired grade = current grade × (1 − final exam weight) + final score × final exam weight. Solving for the final score gives final score = (desired grade − current grade × (1 − final exam weight)) ÷ final exam weight. For example, with a current grade of 78%, a target grade of 85%, and a final exam worth 50% of the class, the required score is (85 − 78×0.5) ÷ 0.5 = (85 − 39) ÷ 0.5 = 92% — that's the score you'd need on the final.
What does it mean if the calculator says I need more than 100%?
A result over 100% means your target grade isn't reachable anymore with the current weighting, because no exam lets you score above a perfect 100%. For example, with a current grade of 70%, a target of 90%, and a final worth only 15% of the class, the required score works out to about 203% — mathematically impossible. In that situation, talk to your instructor about extra credit, dropped grades, or curved scoring, since those are the only ways to change the outcome at this point.
What does "already secured" mean?
If the required score is 0% or lower, you've already secured at least your target grade no matter what you score on the final — even a 0. For example, a current grade of 95%, a target of 80%, and a final worth 10% of the class gives a required score of −55%, meaning your target grade is locked in regardless of the final exam. This can happen when your current work is strong and the final carries relatively little weight.
Is my grade information sent to a server?
No. Every calculation runs entirely in your browser — your current grade, target grade, and exam weight are never uploaded or sent anywhere. Your last entries are saved only in your browser's local storage so they're there when you come back, and this tool has no sign-up, no ads, and no tracking of what you type.
Where do the A, B, and C targets in the table come from?
The table uses common US-style letter grade cutoffs — A at 90%, B at 80%, and C at 70% — to quickly show the score you'd need on the final for each. Grading scales vary widely by school and country (for example, many universities outside the US use different letter cutoffs or a GPA-based scale), so treat the table as a quick reference and check your syllabus for your institution's exact scale.