Average with Weights Calculator
Calculate the weighted mean of any dataset. Assign importance (weights) to each value and get the true average that reflects relative significance.
✓ Add unlimited value-weight pairs
✓ Instant weighted mean
✓ Comparison vs. simple average
Weighted average calculator
Enter values and their weights to compute the weighted mean.
| # | Value | Weight | V \u00d7 W |
|---|---|---|---|
| 1 | 90.00 | 3.00 | 270.00 |
| 2 | 80.00 | 4.00 | 320.00 |
| 3 | 70.00 | 2.00 | 140.00 |
| Total | 9.00 | 730.00 |
What Is a Weighted Average?
A weighted average gives more influence to data points that are more important, frequent, or reliable. Unlike a simple average where every value counts equally, a weighted average reflects the relative significance of each value.
The Formula
Weighted Avg = Σ(value × weight) / Σ(weight)
Values: 80, 90, 70 with weights: 2, 3, 1
(80×2 + 90×3 + 70×1) / (2+3+1) = 500 / 6 = 83.33
Simple average would be (80+90+70)/3 = 80.00 — the 90 with weight 3 pulls the weighted average higher.
Common Use Cases
- Investment portfolio: Returns weighted by position size
- Survey analysis: Responses weighted by demographic group size
- Price indices: CPI weights items by typical consumer spending
- Employee ratings: Evaluation categories weighted by importance
- Manufacturing: Quality scores weighted by production batch size
Weighted vs. Simple Average Example
Portfolio returns:
Stock A: +15% return, $10,000 invested
Stock B: +5% return, $90,000 invested
Simple average: (15+5)/2 = 10% — misleading!
Weighted average: (15×10k + 5×90k) / 100k = 6% — accurate
💡 When Weighted = Simple
If all weights are equal, the weighted average equals the simple average. Weighting only matters when values have different importance or frequency.