Pre-launch planning
Estimate whether your traffic can support an experiment before scheduling it.
Marketing tools
Sample size calculator for conversion tests
Estimate the required sample size per variant from baseline rate, minimum detectable effect, confidence, and power.
How to use
- Enter the baseline conversion rate and minimum detectable effect.
- Select confidence level and power.
- Review the required sample size per variant.
Why this tool is useful
Planning sample size before you launch a test helps prevent underpowered experiments.
This calculator estimates the per-variant requirement using standard normal approximations.
Examples
FAQ
Should I use absolute or relative lift?
This calculator expects minimum detectable effect as a relative uplift percentage.
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