How to use the grade calculator
- Find the grading breakdown in your syllabus (for example homework 20%, quizzes 20%, midterm 25%, final 35%).
- Add a row for each category you have scores for, with your average score and its weight.
- Enter the final exam weight and the class grade you want.
- Read your current grade, the score you need on the final and a table of outcomes.
The formulas
Current grade = Σ (Score × Weight) ÷ Σ Weights so far Needed on final = (Target − Current × (1 − Final weight)) ÷ Final weight Final class grade = Current × (1 − Final weight) + Final score × Final weight
Worked example
- Homework 92% × 20% = 18.4; quizzes 85% × 20% = 17.0; midterm 78% × 25% = 19.5
- Current grade = 54.9 ÷ 0.65 = 84.46% (B)
- For an 85 in the class with a 35% final: (85 − 84.46 × 0.65) ÷ 0.35 = 86% on the final
- For a 90 (A−): 100.3% — just out of reach without extra credit
Standard letter grade scale
| Letter | Percent | Letter | Percent |
|---|---|---|---|
| A+ | 97–100 | C+ | 77–79 |
| A | 93–96 | C | 73–76 |
| A− | 90–92 | C− | 70–72 |
| B+ | 87–89 | D+ | 67–69 |
| B | 83–86 | D | 63–66 |
| B− | 80–82 | D− | 60–62 |
| F | below 60 |
Your teacher’s scale is the one that counts — some use 90/80/70/60 without plus and minus, and some use 94 for an A.
Study smarter for the final
- Know your number: once you know the score you need, you can plan how much to study and where.
- Check dropped scores: many classes drop the lowest quiz or homework, which raises your average.
- Ask about curves and extra credit before the final, not after.
- Prioritise heavily weighted work: a 35% final matters more than a 5% assignment.
- Practice with past exams and focus on topics you lost points on in the midterm.
Points-based grading
Some teachers grade by total points instead of weighted categories: your grade is simply points earned divided by points possible. In that case, enter one row per assignment group with your percentage and use the points possible as the weight — the maths gives the same answer. For the final, use the final’s share of all points in the course as its weight, for example 200 points out of 1,000 = 20%.
What if my final replaces a lower grade?
Some teachers let a strong final exam replace your lowest test score, or count the final more heavily if it helps you. If your syllabus has a rule like this, work out both versions: remove the replaced score from the table, enter the final as an ordinary category with the combined weight, and compare. It is also worth checking how incomplete or missing work is counted — a zero on one 10% assignment pulls the average down far more than a slightly lower test score.