How to use this calculator
- Enter your own values in the labeled fields. Check the units and assumptions before comparing results. Only the fields needed for your selected calculation mode are shown.
- Your answer updates automatically. Review the calculation steps to see exactly how it was calculated.
- Copy, share, save, or download your result. Saved inputs stay on this device.
How the calculation works
Multiply every value by its weight, add those products, and divide by total weight. A zero-weight observation has no effect. Weights can be counts, credits, percentages or other nonnegative quantities, provided they are comparable. They do not need to total one or one hundred.
A worked example
80 with weight 2 and 90 with weight 3 gives (160 + 270) ÷ 5 = 86.
Reading your result
Use the main result together with its units and supporting figures. Display values are rounded; calculations keep their underlying precision. A change in inputs or assumptions can change the answer. Compare the step-by-step working with your intended use before relying on an estimate.
Frequently asked questions
Must weights add to 100?
No. They are normalized by their total.
Can weights be negative?
No. This tool uses nonnegative weights with a positive total.
Sources & methodology
This calculator uses the mathematical identity and assumptions stated above. No current rates, prices, or external data are loaded. Conversion tools use international unit definitions.
Formula review: October 24, 2026. Read our methodology.