Calculate the weighted average by entering up to 10 pairs of value and weight. Add as many entries as you need, click Calculate and get the result instantly.
Weighted Average Calculator
Data
Enter each value and its corresponding weight. The default weight is 1.
How to use the calculator
- Enter the values (e.g. grades) and their corresponding weights in each row.
- Click + Add entry to include more pairs (up to 10).
- Click Calculate. The weighted average will appear in the result field.
- For a new calculation, click Clear.
What is the weighted average
The weighted average is an average where each value has a weight indicating its relative importance. Unlike the arithmetic mean (where all values have equal weight), in the weighted average values with greater weight influence the final result more.
Weighted average formula
WA = Σ(value × weight) ÷ Σweights
Where:
- Σ(value × weight) = sum of each value multiplied by its weight
- Σweights = sum of all weights
Weighted average examples
| Value | Weight | Value × Weight |
|---|---|---|
| 7.0 (Exam 1) | 2 | 14.0 |
| 8.5 (Exam 2) | 3 | 25.5 |
| 9.0 (Assignment) | 1 | 9.0 |
| Σ weights = 6 | Σ(v×w) = 48.5 | |
WA = 48.5 ÷ 6 ≈ 8.08
Frequently asked questions about weighted average
What is the weighted average?
The weighted average is an average where each value has a different weight. Formula: WA = Σ(value × weight) ÷ Σweights. When all weights are equal, the weighted average is identical to the arithmetic mean.
When should I use a weighted average?
Use the weighted average when values have different levels of importance. Examples: grade averages where subjects have different credit weights, price averages with different quantities, or economic indices weighted by market share.
What is the difference between arithmetic mean and weighted average?
In the arithmetic mean, all values have the same weight. In the weighted average, each value has a specific weight indicating its relative importance. The arithmetic mean is a special case of the weighted average where all weights are equal.
How do I calculate the weighted average of grades?
Multiply each grade by its weight, sum all products, and divide by the sum of weights. Example: grade 7 (weight 2) and grade 9 (weight 3) → WA = (7×2 + 9×3) ÷ (2+3) = 41 ÷ 5 = 8.2.
Can I use decimal weights in the weighted average?
Yes. Weights can be any positive number, including decimals such as 0.5 or 1.5. The only requirement is that the sum of weights is not zero.
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