Math

How to Calculate an Average Grade

Learn how to calculate an average grade using equally weighted scores, points earned, credit hours, or weighted course categories.

Updated July 15, 2026

To calculate an average grade, first determine whether all assignments have equal weight. For equally weighted scores, add the grades and divide by the number of grades. When assignments have different point totals, credits, or category weights, use a weighted calculation instead.

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Grade calculationEqual scores and weighted categories use different methods

Check the course grading rules before deciding which average formula to use.

Calculating an average grade Three equal grades of 70, 80, and 90 produce an average of 80.70%80%90%Equal-weight average = 80%

Check How the Course Is Weighted

Before calculating an average grade, determine whether each assignment contributes equally.

Some courses average percentages directly, while others use points, credits, or category weights.

The Average Calculator works for equally weighted grade values.

Equal-Weight Grade Formula

Add all grade percentages and divide by the number of grades.

This method is appropriate only when every score contributes equally.

The result is the arithmetic mean of the grades.

Equal-weight grade formulaAverage grade = Sum of grades ÷ Number of grades

Worked Equal-Weight Example

Suppose the grades are 70 percent, 80 percent, and 90 percent.

Their sum is 240 percentage points.

Dividing 240 by three gives an average grade of 80 percent.

Grade total240
Number of grades3
Average grade80%

Grade Average Based on Points

When assignments have different maximum points, combine the points earned and points available.

Suppose a student earns 18 out of 20 and 70 out of 100.

The combined result is 88 out of 120, or approximately 73.33 percent.

Why Averaging the Two Percentages Can Be Wrong

The first assignment score is 90 percent and the second is 70 percent.

Their simple mean is 80 percent, but that gives the 20-point task the same influence as the 100-point task.

The point-based result of approximately 73.33 percent reflects their actual sizes.

Weighted Category Grades

A course may assign different weights to homework, quizzes, projects, and examinations.

Multiply each category average by its percentage weight and add the results.

Read How to Calculate a Weighted Average for the formula.

Worked Weighted Grade Example

Suppose homework is 20 percent with a score of 90, a project is 30 percent with a score of 80, and an examination is 50 percent with a score of 70.

The weighted contributions are 18, 24, and 35.

The final weighted grade is 77 percent.

Average Grade with Credit Hours

Course grades may also be weighted by credit hours when calculating a programme average.

A six-credit course contributes twice as much as a three-credit course.

Multiply each grade value by its credits and divide by the total credits.

Letter Grades and Grade Points

Letter grades must be converted to the institution's grade-point scale before averaging.

The numeric value assigned to an A, B, or other grade can differ between schools.

Use the official grading policy rather than assuming a universal conversion.

Rounding the Final Grade

Avoid rounding individual category contributions too early.

Keep several decimal places during the calculation and round only the final result.

Follow the institution's rule for decimal places and grade boundaries.

Common Mistakes

Do not assume all assignments have equal weight.

Do not average percentages from assignments with very different point totals unless the course rules allow it.

Do not apply an unofficial letter-grade conversion.

Conclusion

Use a simple average when all grades are equally weighted.

Use combined points, percentage weights, or credit hours when contributions differ.

Use the Average Calculator for equal-weight scores.

FAQs

How do I average equally weighted grades?

Add the grade values and divide by the number of grades.

What if assignments have different point totals?

Add points earned and divide by the combined points available.

How do weighted categories work?

Multiply each category score by its percentage weight and add the contributions.

Should I round every assignment score?

Keep precision during the calculation and round the final result.

Can letter grades be averaged directly?

Convert them using the institution's official grade-point scale first.

Calculate the average

Enter your values to calculate the arithmetic mean and supporting statistical results.

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