What 40-40-20 means
In a 40-40-20 semester, quarter 1 and quarter 2 each make up 40% of the grade and the final exam makes up the other 20%. The quarters together are 80% of the grade, so most of it is settled before the exam. The exam can move your grade by at most 20 points: a 0% adds nothing and a 100% adds 20 points.
40-40-20 formula
Semester grade = Q1 × 0.4 + Q2 × 0.4 + Exam × 0.2
Exam needed = (Target − Q1 × 0.4 − Q2 × 0.4) ÷ 0.2
Example: 88% and 84% before the exam
The quarters give 88 × 0.4 + 84 × 0.4 = 68.8 points. For a 90% (an A) the exam has to add 21.2 points, so you would need 106%, which is not possible without extra credit. For an 80% (a B) the exam has to add 11.2 points: 56%.
Exam score needed for each grade (40-40-20)
| Quarter average | A (90%) | B (80%) | C (70%) | D (60%) |
|---|---|---|---|---|
| 95% | 70% | 20% | Locked in | Locked in |
| 90% | 90% | 40% | Locked in | Locked in |
| 85% | Out of reach | 60% | 10% | Locked in |
| 80% | Out of reach | 80% | 30% | Locked in |
| 75% | Out of reach | 100% | 50% | Locked in |
| 70% | Out of reach | Out of reach | 70% | 20% |
| 65% | Out of reach | Out of reach | 90% | 40% |
How much the final exam can move your grade
| Quarter average | Exam 0% | Exam 50% | Exam 100% |
|---|---|---|---|
| 95% | 76% | 86% | 96% |
| 90% | 72% | 82% | 92% |
| 85% | 68% | 78% | 88% |
| 80% | 64% | 74% | 84% |
| 75% | 60% | 70% | 80% |
| 70% | 56% | 66% | 76% |
| 65% | 52% | 62% | 72% |
Quarter average you need for each grade (40-40-20)
- A: possible from a quarter average of 87.5% if you get 100% on the exam. No quarter average keeps it safe with a 0 on the exam.
- B: possible from a quarter average of 75% if you get 100% on the exam. Only a perfect 100% quarter average keeps it safe with a 0 on the exam.
- C: possible from a quarter average of 62.5% if you get 100% on the exam. With a quarter average of 87.5% or more it is safe even with a 0 on the exam.
- D: possible from a quarter average of 50% if you get 100% on the exam. With a quarter average of 75% or more it is safe even with a 0 on the exam.
40-40-20 vs 45-45-10
With 45-45-10, the exam counts 10% instead of 20%, so it can move your grade by at most 10 points and the quarters decide almost everything. With 40-40-20, a strong exam matters more: an A is still possible from a quarter average of 87.5%, against 88.89% with 45-45-10. A weak exam also costs more, so the safe zone for a 0 on the exam is smaller.
Check your school’s rules
Some schools round each quarter grade before combining them, set a minimum exam score to pass, or let students with high grades skip the exam. This calculator uses the exact grades you enter and the standard scale (A 90%, B 80%, C 70%, D 60%). If your quarters do not count equally, change the weights in the calculator.
Key terms explained
- Quarter grade
- Your percentage grade for one nine-week grading period.
- Semester exam
- A cumulative exam that counts as a fixed share of the semester grade.
- Weight
- The percentage of the semester grade that each part contributes.