How to Calculate a Grade Average

A grade average is just the mean of your scores — add them up and divide by how many there are — unless some assignments are weighted, in which case you account for that. Knowing which kind you need is the whole trick. Our free grade average calculator handles both simple and weighted averages for you.

Simple average

When every assignment counts equally, use a plain average: add all your scores and divide by the number of scores. This is the right method for, say, a set of quizzes that are each worth the same.

A worked example

Suppose your quiz scores are 88, 92, 79, and 95. Add them: 88 + 92 + 79 + 95 = 354. Divide by 4 quizzes: 354 / 4 = 88.5. Your average is 88.5%. Quick and clean when everything carries the same weight.

Weighted average

When assignments count for different amounts, multiply each score by its weight and add those products. For example, if homework (90%) is worth 30% and a test (80%) is worth 70%, your average is (0.30 x 90) + (0.70 x 80) = 27 + 56 = 83%. The heavier test pulls the result toward its score.

Which one do you need?

• Simple average — use it when all scores carry equal weight.
• Weighted average — use it when categories or assignments are worth different percentages.
• Check your syllabus to see which applies; mixing them up is the most common error.

Dropping the lowest score

Some teachers drop your lowest score before averaging. If yours does, remove that score first, then average the rest. It's a small step that can noticeably lift your number — just confirm the policy applies to your class, since it varies.

Average your grades the easy way

Drop your scores into the grade average calculator, and when you're ready to turn averages into a full course grade, use the semester grade calculator. For help bringing up a low average, COSMIQ's free voice tutor is free for every student.

Related resources: grade average calculator · semester grade calculator · free voice tutor