Power Analysis Calculator

Written by Great Medico

Updated September 24, 2026 1 min read

Study group design

Primary endpoint

Group 1 anticipated incidence (%)

Group 2 / population anticipated incidence (%)

Group 1 mean

Group 1 standard deviation

Group 2 / population mean

Group 2 standard deviation

Effect size

Effect change (%)

Enrollment ratio (group 2 : group 1)

Alpha (α)

Power (%)

Your Result

—

Ready to calculate

Enter values and click Calculate.

Important: This normal-approximation result is for study planning; use a design-specific analysis for clustered, survival, repeated-measure, or adjusted models.

See an error or outdated claim? We welcome correction requests. Request a correction Editorial policy

Your feedback

Was this article helpful?

Your answer helps us improve the clarity and usefulness of our health content.