How to Calculate Grades
A comprehensive guide to understanding different grade calculation methods.
Common Grade Calculation Methods
Weighted Category Method
Different categories of assignments (homework, exams, projects) are given different weights based on importance.
Formula:
Final Grade = Σ(Category Average × Category Weight)
For example: If tests are 40%, homework is 30%, and a final exam is 30%, your final grade would be:
(Test Average × 0.4) + (Homework Average × 0.3) + (Final Exam × 0.3)
Total Points Method
Each assignment is worth a certain number of points, and your grade is determined by the percentage of total possible points earned.
Formula:
Final Grade = (Points Earned ÷ Total Possible Points) × 100%
For example: If you earned 850 points out of 1000 possible points:
(850 ÷ 1000) × 100% = 85%
Step-by-Step: Weighted Category Method
Let's calculate a final grade using the weighted category method with the following structure:
- Tests: 40% of final grade
- Homework: 25% of final grade
- Quizzes: 15% of final grade
- Final Exam: 20% of final grade
Calculate the average for each category
Category Scores Average Tests 78%, 85%, 92% 85% Homework 100%, 90%, 95%, 88%, 92% 93% Quizzes 70%, 85%, 90%, 75% 80% Final Exam 88% 88% Multiply each category average by its weight
Category Average Weight Weighted Score Tests 85% 40% 85 × 0.4 = 34.0 Homework 93% 25% 93 × 0.25 = 23.25 Quizzes 80% 15% 80 × 0.15 = 12.0 Final Exam 88% 20% 88 × 0.2 = 17.6 Add all weighted scores to get the final grade
34.0 + 23.25 + 12.0 + 17.6 = 86.85%
Final Grade: 86.85% (B based on most standard grading scales)
Step-by-Step: Total Points Method
Let's calculate a final grade using the total points method with the following assignments:
| Assignment | Points Earned | Points Possible |
|---|---|---|
| Homework 1 | 45 | 50 |
| Homework 2 | 48 | 50 |
| Quiz 1 | 18 | 20 |
| Quiz 2 | 17 | 20 |
| Midterm | 86 | 100 |
| Project | 92 | 100 |
| Final Exam | 142 | 150 |
| Totals | 448 | 490 |
Calculate total points earned and total points possible
Total Points Earned: 448
Total Points Possible: 490
Divide points earned by points possible and multiply by 100%
(448 ÷ 490) × 100% = 91.43%
Convert percentage to letter grade based on grading scale
Final Grade: 91.43% (A- on most standard grading scales)
Calculating Your Current Grade
To calculate your current grade during a term when not all assignments have been completed:
For Weighted Categories
- Calculate your current average for each category based on completed assignments
- If a category has no grades yet, either:
- Exclude it and adjust other weights proportionally, or
- Make a projection based on your performance in other categories
- Apply the weights to calculate your current standing
For Total Points
- Sum all points earned so far
- Sum all points possible so far (only for completed assignments)
- Divide points earned by points possible and multiply by 100%
- This gives your current percentage grade based on completed work
Special Grade Calculations
Calculating Needed Scores
To determine what score you need on upcoming assignments to achieve a desired final grade:
| Method | Formula |
|---|---|
| For Final Exam | Required Score = (Desired Final Grade - Current Grade × (1 - Exam Weight)) ÷ Exam Weight |
| For Total Points | Required Points = (Desired % × Total Possible Points) - Points Already Earned |
Use our Final Grade Calculator to determine what score you need on your final exam.
Dropped Assignments
If your course allows dropping the lowest scores:
- For each category with dropped assignments, identify your lowest scores
- Remove these scores from your calculations
- Recalculate your category averages using only the remaining scores
- Apply the standard grade calculation method with these adjusted averages
Extra Credit
There are two common ways to incorporate extra credit:
- Added to category: Extra credit points are added to a specific category total
- Added to final grade: Extra credit points are added after calculating the regular final grade
Check your course syllabus or ask your instructor to confirm how extra credit is handled.
Grade Calculation Tools
Use our suite of calculators to help you track and plan your grades: