How do I work out what I need on my final?
- 1Choose whether you want the score you need on the final, or your overall grade after it.
- 2Enter your current grade in the course, as a percentage.
- 3Enter how much the final exam is worth — the weight from your syllabus.
- 4Enter the overall grade you want (or the score you got on the final) and read the answer, with every step.
What is the formula for a final grade?
- 01w = final exam weight ÷ 100
- 02Overall grade = current grade × (1 − w) + final score × w
- 03Score needed on the final = (wanted grade − current grade × (1 − w)) ÷ w
Most courses work out your grade as a weighted average. If the final exam is worth 30%, everything before it is worth the other 70%. So your overall grade is 70% of your current grade plus 30% of your final exam score.
To find the score you need, turn that around: take the grade you want, subtract the points you've already earned (current grade × 70%), and divide what's left by the final's weight (0.30). Example: 85% now, final worth 30%, want 90% → (90 − 85 × 0.7) ÷ 0.3 = (90 − 59.5) ÷ 0.3 = 101.7% — just out of reach.
If the answer is above 100%, the target can't be reached without extra credit. If it is 0% or below, you already have the grade. The table shows your overall grade for every final score from 0% to 100%, so you can see what each 10 points on the final is worth.
What do I need on my final to get a 90?
With a current grade of 85%, a final worth 30% and a goal of 90%, you have already secured 59.5% of your course grade.
The final must add 30.5%, so you need 101.67% on the final. The best you can still get is 89.5%.
Good to know
- Check the syllabus for the exact weight of the final — 25% and 40% give very different answers.
- Aim a few points above the score you need, as a safety margin for a hard paper.
- If the score needed is over 100%, ask about extra credit or how the course rounds grades.
- Your current grade must already include every assignment before the final for the answer to be right.
Final exam grade questions
How do I calculate what I need on my final exam?
Score needed = (grade you want − current grade × (1 − w)) ÷ w, where w is the final's weight as a decimal. With 80% now, a final worth 25% and a goal of 85%: (85 − 80 × 0.75) ÷ 0.25 = 100%.
How much will my final exam affect my grade?
Exactly by its weight. If the final is worth 20%, every 10 points you score on it adds 2 points to your course grade. The table above shows your grade for each final score.
What if I need more than 100% on the final?
Then you can't reach that grade with the final alone. Look at the highest grade still possible (the 100% row), and ask your teacher about extra credit or re-sits.
Can I fail the class if I fail the final?
Look at the 0% row: that's your grade if you score nothing. If it is above the pass mark you can still pass on points — but some courses also require you to pass the final itself, so check the syllabus.
What do I need on my final to get an A?
Enter the A cut-off (often 90%, or 93% for a full A at some schools) as the grade you want, with your current grade and the final's weight, to see the score you need.
Does this work with points instead of percentages?
Yes, if you turn points into percentages first: current grade = points earned ÷ points possible so far × 100, and weight = final exam points ÷ total course points × 100.
Sources
- Weighted arithmetic mean — the average that weighted course grades use
- BigFuture (College Board) — how grades and GPA are calculated
Formulas last reviewed: September 30, 2026 ·How we check our formulas