How does the Effect Size Calculator work?

Cohen's d = (μ1 - μ2) / σ (standardized mean difference) Then: d 0.8: large Then: Also: Pearson r for correlation, η² for ANOVA Then: Complements p-values (which depend on n).

Can you give an example of how to use the Effect Size Calculator?

Example: Input Mean diff 5, σ 2 gives a result of d=2.5.

Is the Effect Size Calculator free to use?

Yes — completely free with no registration, download, or subscription required. All calculations happen instantly in your browser.

How accurate is the Effect Size Calculator?

Our Effect Size Calculator uses verified mathematical formulas and is accurate to multiple decimal places. Results are calculated in real-time using the same methods used by professionals.

Matematica

Effect Size Calculator

Effect Size (Cohen's d, Hedges\' g)

Mean 1

Mean 2

SD 1

SD 2

Calculates effect size (magnitude of effect) independent of sample size.

Symbol	Name	Unit	Description
d	(μ1 - μ2) / σ (standardized mean difference)	—	(μ1 - μ2) / σ (standardized mean difference)

Difficulty:intermediate

⭐

Did You Know?

Large sample with d = 0.1 (tiny effect) may be significant but practically meaningless.

References

›Effect Size Calculator

🔒

100% Gratuito

Nessuna registrazione

✓

Preciso

Formule verificate

⚡

Istantaneo

Risultati immediati

📱

Compatibile mobile

Tutti i dispositivi

Effect Size Calculator

Effect Size (Cohen's d, Hedges\' g)

Cos'è Effect Size Calculator?

Formula

Leggenda delle variabili

Come Effect Size Calculator

Esempi risolti

Applicazioni pratiche

Domande frequenti

Errori comuni da evitare

Impostazioni