Effect Size Calculator

Convert Cohen's d, r, odds ratio, eta-squared, and Cohen's f with assumptions shown.

Group-size assumption

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Assumptions appear in the table.

Converted effect sizes
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r = d / sqrt(d^2 + 4), OR = exp(d * pi / sqrt(3)) How?

How this is calculated

Equal-group conversions use the standard relationship between Cohen's d and the point-biserial correlation. Odds-ratio conversion uses Chinn's logistic approximation, so the table marks it as an approximation.

Formula: r = d / sqrt(d^2 + 4), OR = exp(d * pi / sqrt(3))

Sources

  1. Effect size overview. Wikipedia. Retrieved .
  2. Chinn odds-ratio approximation. Statistics in Medicine. Retrieved .

Method last reviewed