Weighted Average Calculator

WA = Σ(value × weight) / Σ(weight). Generalizes the arithmetic mean.

Inputs

Result

Weighted average
87.2000
Σweights = 1.0000; arithmetic mean = 86.2500.
  • Pairs4
  • Σ(v×w)87.2000
  • Σ(w)1.0000
  • WA87.200000
  • Arithmetic86.250000

Step-by-step

  1. Σ(value × weight) = 85×0.2 + 90×0.3 + 78×0.2 + 92×0.3 = 87.2000.
  2. Σ(weight) = 0.2 + 0.3 + 0.2 + 0.3 = 1.0000.
  3. WA = 87.2000 / 1.0000 = 87.2000.

How to use this calculator

  • Enter values + corresponding weights.
  • Weights need not sum to 1 (formula normalizes).

About this calculator

Weighted average: each value contributes proportionally to its weight. Used for: GPA (course credits = weights), portfolio returns (asset values = weights), survey responses with population adjustment, course grade with categories of different weights. If all weights equal, reduces to arithmetic mean.

Frequently asked

Convenient but not required. Formula divides by Σweights, so any positive weights work.

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