Sample-size calculator
Plan a trustworthy experiment before you ship the toggle. Enter your baseline, the minimum effect you care about, your target power and significance, and we'll compute the sample size you need per variant, how many days that takes at your traffic, and the pitfalls to avoid (peeking, sample-ratio mismatch, weekly seasonality). It computes — it never mutates.
Sample-size calculator
Power analysis · per-variant N · days to significance · design guidance
free
Enter your design parameters
Get the per-variant sample size, days to significance, recommended metrics/duration and the pitfalls to avoid.