Foundations Experimentation
Statistical power calculator
Plan your experiment's sample size.
Enter your baseline conversion rate and minimum detectable effect to calculate the
sample size needed, or provide a sample size to find the detectable effect.
Why do I need a power analysis?
If your experiment doesn't have a large enough sample, you might not be able to detect a meaningful effect, even if one exists. Power analysis helps you determine the right sample size to confidently identify whether your experiment's results are due to chance or a real effect.
The power analysis tool has two modes:
Solve for sample size: Input your baseline conversion rate, minimum detectable effect, significance level, and desired power to calculate the required sample size per group.Solve for MDE: Input your baseline conversion rate, sample size per group, significance level, and desired power to calculate the minimum detectable effect.