Math

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Weighted Average Calculator.

Calculate a weighted mean from matching comma-separated values and weights.

On-device calculationNo signup
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Set your values

Results update as you type.

Weighted average: 20

Weighted average

0.000000
Total weight: 4

Total weight

0.000000

Results update automatically as you type.

Use Cases

Academic Grade Calculation

Determine your overall course grade by weighting assignments, quizzes, and exams according to their percentage contribution.

Example: Homework (weight 20) score 85, Midterm (weight 30) score 90, Final (weight 50) score 80.

Financial Portfolio Returns

Calculate the average return of a portfolio where each investment has a different proportion of the total portfolio.

Example: Stocks (weight 60%) return 8%, Bonds (weight 40%) return 3%.

Frequently Asked Questions

How do I use the weighted average calculator?
Enter your values in the 'Values' field and their corresponding weights in the 'Weights' field. The calculator will compute the weighted average by multiplying each value by its weight, summing these products, and dividing by the sum of the weights.
What is the difference between weighted average and simple average?
A simple average treats all values equally, while a weighted average assigns different importance (weights) to each value. This calculator uses the weights you provide to reflect the relative significance of each value.
Can the weights be any numbers?
Yes, weights can be any positive numbers. They do not need to sum to 1 or 100. The calculator normalizes them automatically by dividing by the total weight.

Tips & Common Mistakes

Tips

  • Ensure each value has a corresponding weight. The number of weights must match the number of values.
  • Weights can be percentages (e.g., 20, 30, 50) or any relative numbers; the result is the same.
  • Double-check your inputs for typos, as the calculator computes instantly and does not validate data.
  • Use the weighted average when some data points are more important than others, not when all are equal.

Common Mistakes to Avoid

  • Mismatching the number of values and weights, which can lead to an error or incorrect result.
  • Using negative weights, which are not meaningful in most contexts and can distort the average.
  • Forgetting to include all relevant values, especially when weights sum to 100% but some values are missing.

Last updated: August 13, 2026