Weighted Average

Compute a weighted mean from a list of values and corresponding weights

About this calculator

The Weighted Average Calculator computes a weighted mean from a list of values and their weights: Σ(value × weight) ÷ Σ(weights). Weights don't need to sum to 1 — the calculator normalizes them and shows each entry's share of the total. It reports the weighted sum, the total weight, and the weighted average, all computed with 30-digit precision. Blank or malformed rows are skipped, and an all-zero weight set is flagged rather than divided by. Useful for course grades, GPAs, portfolio returns, and survey scores.

How to use the Weighted Average calculator

  1. Enter the values for your problem into the input fields.
  2. Read the result — it updates instantly as you type.
  3. Check the formula and the visual explanation to follow how the answer was found.
  4. Copy the page URL to share the exact calculation.

Common examples

  • Scores 90, 80, 70 with weights 0.5, 0.3, 0.2 → weighted average 83
  • Grades 85, 92, 78 weighted 2, 3, 5 → weighted sum 836, total weight 10 → average 83.6
  • GPA: grade points 4, 3, 3.7 with credit weights 3, 4, 3 → 35.1 ÷ 10 = 3.51
  • Values 3 and 4 with weights 1 and 3 → 15 ÷ 4 = 3.75 (weight shares 0.25 and 0.75)

Frequently asked questions

How does the Weighted Average calculator work?

Enter your values and the calculator applies the exact mathematical method for this problem, showing the result together with the formula it used. Everything is computed with high-precision arithmetic, so the answer you see is not limited by ordinary floating-point rounding.

When would I use the Weighted Average calculator?

It is useful for homework and exam preparation, for checking work done by hand, and whenever a step in a larger problem needs this calculation done quickly and reliably.

How accurate are the results?

Calculations run at 30 significant digits of precision internally. Displayed values are rounded for readability, but the underlying result is far more precise than a typical hand or pocket-calculator computation.

Can I share a specific calculation with someone else?

Yes. Every value you enter updates the URL, so copying the address bar and sharing the link reopens the exact same calculation for whoever clicks it.