How to Calculate Your Class Grade

Your total class grade percentage is the weighted average of your homework, quiz, and test scores. The weights of each component are determined by your instructor; midterm exams and the final exam usually count for much more than homework assignments and quizzes.

If you want to compute your class grade as a percent, you can follow the explanation presented below, or use the convenient grade calculator on the left. How you convert a percent grade to a letter grade depends on your teacher's policies and whether or not there is a curve. A commonly applied letter grade scale is shown at the bottom of the page.

Step 1
Check your syllabus to see how much homework, quizzes, tests, and the final exam count toward your total class grade. Express these weights as decimals. For example, suppose homework is 10% of your grade, quizzes 16%, the two mid-terms 22% each, and the final 30%. Then the weights are 0.10, 0.16, 0.22, 0.22, and 0.30 respectively. (If using the calculator, do not convert any percents to decimals; the calculator does this for you.)

Step 2
Review your grades and convert them to decimals as well. For example, suppose your average homework grade is 88%, average quiz grade 79%, first exam score 97%, second exam score 83%, and final exam score 93%. Then the decimal equivalents are 0.88, 0.79, 0.97, 0.83, and 0.93.

Step 3
Multiply each component score by its weight, then add all the numbers to calculate your total class grade as a decimal. Using the example above, you would compute

(0.10)(0.88) + (0.16)(0.79) + (0.22)(0.97) + (0.22)(0.83) + (0.30)(0.93)
= 0.088 + 0.1264 + 0.2134 + 0.1826 + 0.279
= 0.8894

Step 4
Convert this to a percent by moving the decimal point two units to the right. In this example, 0.8894 is equivalent to 88.94%. According to the grading scale shown below, this is a B+.

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