Some teachers give you regular updates on your overall class grade. But if you want to keep track of your own progress, or if you have a teacher who doesn't fill you in very often, you can calculate your own grades using simple math. In order to figure out your class grade, you'll need to know how many points you've scored out of how many possible, and whether your teacher uses a weighted average to calculate your final grade.
TL;DR (Too Long; Didn't Read)
If your teacher doesn't use weighted averages, you can calculate your class grade with the simple formula:
(points earned ÷ points possible) × 100 = class grade in percentage form
Calculate My Grade: Basic Version
If your teacher doesn't use weighted averages, all you have to do to calculate your class grade is add up the number of points you earned on all tests and quizzes, as well as the number of points that were possible, and then divide the points earned by points possible. As a formula, for a percentage grade, this means:
So if you took three tests and scored 75/100, 80/100 and 95/100 points on them, what is your grade so far?
Your total points earned are:
And your total points possible are:
So your class grade, so far, is:
Right now your result is in decimal form, but it'll be easier to read if you multiply it by 100 to convert it to percentage form:
So, your class grade is 83 percent.
Sometimes, not every test has the same amount of points available – but the formula for finding your class grade remains the same. What if you've taken four tests so far, receiving 42/50, 33/40, 56/60 and 21/25 points respectively? The steps for calculating your class grade don't change:
Your total points earned are:
Your total points possible are:
So your class grade (so far) is:
Multiply by 100 to convert the decimal result into percentage form:
So your class grade, so far, is 87%.
Be Your Own Weighted Average Calculator
There's another wrinkle: Sometimes teachers will use a weighted score or weighted average to figure their class grades, which means that some of your scores are more important for your final score than others. For example, your teacher might say that tests make up 80 percent of your grade, with homework counting for the remaining 20 percent.
When you deal with weighted grades, you calculate a grade for each scoring category as already described, dividing the total points earned by total points possible – and then you add an extra step.
Divide points earned by points possible to calculate your grade in each scoring category. So if you've earned 280 points out of 300 points possible on tests, you'd have:
And if you were diligent in your homework and got 295 points out of 300 possible, you'd have:
Note that for now, you're leaving the results in decimal form.
Next, multiply the grade in each scoring category by the appropriate weighted percentage. Go ahead and leave the weighted percentage in decimal form. This gives you:
(because tests are worth 80% or 0.8 of your grade), and
(because homework is worth 20% or 0.2 of your grade).
Add together the weighted grades for each scoring category. The result is your overall weighted grade. So, you have:
But the result is still in decimal form. Go ahead and multiply by 100 to convert it to an easier-to-read percentage:
After calculating the weighted average, your class grade is 94.3%.
About the Author
Lisa studied mathematics at the University of Alaska, Anchorage, and spent several years tutoring high school and university students through scary -- but fun! -- math subjects like algebra and calculus.
Jeffrey Coolidge/Digital Vision/Getty Images