Weighted Average Calculator
By Santaji GadepatilinUpdated October 27, 2026
A weighted average gives some values more importance than others. It is used for grades, portfolio returns and average prices.
How to use the weighted average calculator
Enter up to five values and their weights. Leave unused rows with a weight of 0. The calculator shows the total weight and the weighted average.
Weighted average formula
Weighted average = Σ(xᵢ × wᵢ) ÷ Σwᵢ
Example: course grade
| Component | Score | Weight | Score × weight |
|---|---|---|---|
| Assignments | 85 | 30% | 25.5 |
| Midterm | 72 | 20% | 14.4 |
| Final exam | 90 | 50% | 45.0 |
| Total | 100% | 84.9 |
The weighted grade is 84.9, while the simple average of 85, 72 and 90 is 82.3.
Common uses
| Use | Values | Weights |
|---|---|---|
| Course grades | Scores | Percentage weights or credits |
| GPA / CGPA | Grade points | Credit hours |
| Average purchase price | Prices | Quantities bought |
| Portfolio return | Asset returns | Amount invested in each |
| Survey ratings | Rating levels (1–5) | Number of responses |
Weighted price example
Buying 100 units at 20 and 300 units at 24 gives a weighted average price of (2,000 + 7,200) ÷ 400 = 23, not the simple average of 22. See the stock average calculator for share purchases.
Weighted vs arithmetic mean
If all weights are equal, the weighted average equals the ordinary average.
Frequently asked questions
How do I calculate a weighted average?
Multiply each value by its weight, add the products, then divide by the sum of the weights.
Do the weights have to add up to 100?
No. The calculator divides by the total of the weights, so you can use percentages, credits, quantities or any positive numbers.
What is the difference between a weighted and a simple average?
A simple average treats every value equally. A weighted average gives more influence to values with larger weights.
How do I ignore an unused row?
Leave its weight at 0.