Weighted Average Calculator
Compute a weighted average from a list of values and a matching list of weights. Each value counts in proportion to its weight, so heavier items pull the average more.
What this calculator does
The Weighted Average Calculator estimates your result instantly from the values you enter, using standard math & conversions formulas. Compute a weighted average from a list of values and a matching list of weights. Each value counts in proportion to its weight, so heavier items pull the average more. Calculations run in your browser, so nothing you type is sent to a server, and the output is an estimate rather than a certified or official figure.
Result
About Weighted Average Calculator
A weighted average lets some numbers count more than others. This tool multiplies each value by its matching weight, adds those products, and divides by the total of the weights.
Enter the values and the weights as two comma-separated lists of equal length; the total weight cannot be zero.
Formula & Mathematical Calculation
Weighted Average = f(Values (comma-separated), Weights (comma-separated))
Calculated according to standard math formulas implemented in the calculator core.
Calculation Example
Enter values 80,90,70 and weights 2,3,1, then press Calculate. The tool computes (80×2 + 90×3 + 70×1) ÷ (2+3+1) = 500 ÷ 6 = 83.3333. It shows Weighted Average = 83.3333, with the note "Weighted average = sum(value x weight) / sum(weights) = 83.3333."
Key Benefits
- Applies each weight to its value automatically, so grades or scores with different importance combine correctly.
- Checks that the value and weight lists match in length before calculating.
- Rounds the result to four decimals and runs free in the browser with no sign-up.
How to Use this Calculator
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Enter the values
Type your numbers into the Values (comma-separated) field, for example 80,90,70. -
Enter the weights
Type one weight per value into the Weights (comma-separated) field, such as 2,3,1. -
Calculate
Press Calculate to see the Weighted Average.
Assumptions & Limitations
What the calculation assumes
- Every value you enter is treated as an exact, known amount.
- Any rate or interval you enter is assumed to hold for the whole period unless the form asks for it separately.
- Results use standard published formulas and account only for the values entered above.
- Rounding is applied for display; the underlying calculation uses your full precision.
- Results are returned in the same units you enter, unless the tool states the output unit.
What it does not cover
- Weighted Average Calculator produces a calculated result for reference and learning, not a certified or official measurement.
- Real-world outcomes differ when tolerances, rounding rules or local standards apply.
- Definitions and standards vary by region and change over time; verify the convention that applies to your case.
- Figures are only as accurate as the inputs you supply — check them before acting on the result.
- For work where the result carries real consequences, confirm it against an authoritative source.
Frequently Asked Questions
Free to use, no account needed. Calculations run in your browser, so nothing you type is sent to a server. Results are estimates — how we build and check our calculators.