Weighted Average Calculator
Add each value with its weight (credits, percent of grade, quantity) and get the weighted mean with the working shown.
Weighted mean formula
x̄w = Σ(wᵢ · xᵢ) ÷ Σwᵢ
An ordinary mean gives every value a weight of 1. A weighted mean lets some values count more, which is what you want when a final exam is worth half the grade, when a 4-credit course should matter more than a 1-credit course, or when averaging prices bought in different quantities.
Common mistake: averaging averages
If class A (30 students) averaged 70 and class B (10 students) averaged 90, the combined average is not 80. Weight by class size: (30×70 + 10×90) ÷ 40 = 75.
Frequently asked questions
How do I calculate a weighted average?
Multiply each value by its weight, add those products, then divide by the sum of the weights. For grades of 88 (20%), 76 (30%) and 92 (50%): (88×20 + 76×30 + 92×50) ÷ 100 = 86.4.
Do the weights have to add up to 100?
No. The formula divides by the total weight, so weights of 2, 3 and 5 give exactly the same answer as 20%, 30% and 50%. Credits, quantities and percentages all work.
How do I work out what I need on the final exam?
Enter your known grades and weights, then add a row for the final with its weight and try values until the weighted average reaches your target. Algebraically, needed score = (target × total weight − current Σ value×weight) ÷ final weight.
Is GPA a weighted average?
Yes. GPA weights each course’s grade points by its credit hours. Enter grade points as values and credits as weights.