Weighted Average Calculator
Calculate a weighted average (weighted mean) from a list of values and their weights.
How it works
- 1Enter your values, separated by commas or spaces.
- 2Enter a matching list of weights in the same order.
- 3The weighted average is the sum of value × weight divided by the sum of weights.
Use cases
- Compute a course grade from weighted categories.
- Average ratings where some count more than others.
- Blend metrics with different importance.
Frequently asked questions
What is a weighted average?
An average where each value contributes in proportion to its weight: Σ(value × weight) ÷ Σ(weight). Heavier weights pull the result toward their values.
What if I have a different number of values and weights?
Each value needs exactly one weight, so the two lists must be the same length. Otherwise the result shows "—".
Can weights be decimals or percentages?
Yes. Weights can be any numbers; only their relative sizes matter.
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