Óscar's A/B Testing Toolkit

A/B Test Sample Size/Duration Calculator

Plan your A/B tests with confidence!

How many users will see the experiment every day?
The expected (conversion, sign-up…) rate for your control group.
The smallest improvement you want to detect. Detecting smaller changes requires more data.

Duration

50

days to complete

Sample size

24,601

per variant

The experiment will need to run for 4 months and 9 days to detect a 10% improvement (from 3.0% to 3.3%).

Detectable Δ (%) From → To Duration Visitors/variant
Days Visitors/variant Detectable Δ From → To