Weighted Average Calculator

Calculate a weighted average for values that do not all count equally. Each row has a Value and Weight, and the calculator returns the weighted average, total weight, number of entries, and a breakdown of each value times weight.

How to use this calculator

Enter each value in the Value field.
Enter that value’s importance in Weight.
Add or remove entries as needed, up to 100 rows.
Review the weighted average and weighted products.

Weights can be percentages, points, credits, hours, or shares. They do not need to add to 100, but they should use one consistent scale.

Formula

$Weighted\ Average = Σ(Value × Weight) ÷ Σ(Weights)$

The calculator multiplies each value by its weight, adds those products, then divides by total weight.

Worked example

Suppose scores are 90 with weight 20, 85 with weight 50, and 95 with weight 30.

$((90 × 20) + (85 × 50) + (95 × 30)) ÷ (20 + 50 + 30) = 89$

The weighted average is 89.

When weights matter

Weighted averages are useful for grades, portfolios, survey scoring, and performance metrics where some entries matter more than others. For course-specific GPA weighting, use the weighted GPA calculator. For unweighted summaries such as mean and median, use the statistics calculator. For percentage inputs, the average percentage calculator may be a better fit.

Frequently asked questions

How do I calculate a weighted average?

Multiply each value by its weight, add those products, then divide by the total of all weights.

Do weights have to add up to 100?

No. Weights can be points, credits, percentages, or any nonnegative scale as long as all rows use the same kind of weight.

What inputs does this calculator use?

Each row has a Value and a Weight. You can add up to 100 entries, and the calculator also shows weighted products.

What happens if all weights are zero?

The calculator cannot divide by a total weight of zero, so it asks for a positive total weight.