Weighted Average Calculator

Reviewed by CalcMulti Editorial Team·Last updated: February 2026·← Statistics Hub

The weighted average (weighted mean) assigns different levels of importance to each value in a dataset. Unlike the simple arithmetic mean which treats every value equally, a weighted mean multiplies each value by its weight before averaging — producing a result that reflects how much each value should count.

Enter your values and their corresponding weights to calculate the weighted mean instantly. Use it for GPA calculations, portfolio returns, survey aggregation, or any scenario where observations differ in importance.

How the weighted mean is calculated: multiply each value by its weight, sum the products, then divide by the total weight. Formula: x̄_w = Σ(wᵢ × xᵢ) / Σwᵢ. The weights do not need to sum to 1 or 100 — any positive numbers work. If weights are percentages summing to 100, the denominator is 100. If weights are counts or frequencies, the formula becomes equivalent to the regular mean of the full dataset.

Worked example — GPA calculation: Grades of A (4.0), B (3.0), A (4.0), C (2.0) for courses worth 3, 4, 3, 2 credit hours respectively. Weighted sum = 4.0×3 + 3.0×4 + 4.0×3 + 2.0×2 = 12 + 12 + 12 + 4 = 40. Total credits = 3 + 4 + 3 + 2 = 12. Weighted GPA = 40/12 = 3.33. The simple mean of the four grades would be (4+3+4+2)/4 = 3.25 — lower because the 4-credit B course carries more weight than the 2-credit C.

Common use cases: GPA and academic performance (credit-hour weights), portfolio returns (dollar-value weights), survey results when samples are not representative (demographic adjustment weights), financial indices (market-cap weights in the S&P 500), scientific measurements with varying precision (inverse-variance weights), and moving averages in technical analysis (exponential weights favoring recent data).