Cohen's d Effect Size Calculator

Calculate Cohen's d from two-group means, standard deviations, and sample sizes with pooled-SD approach.

Quick Facts

Core Formula
d=(m1-m2)/spooled
Use this for planning estimates and sanity checks.

Your Results

Calculated
Cohen's d
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Primary output
Pooled SD
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Secondary output
Magnitude Label
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Verification metric
Interpretation Note
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Interpretation

Ready

Enter values and calculate to get scenario outputs.

How This Calculator Works

This calculator is scoped for practical scenario analysis with concise outputs that are easy to compare.

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