Minimum Detectable Effect (MDE) Calculator
Work backward from the traffic you can collect to the smallest relative conversion-rate lift your two-arm test is powered to detect.
9.9%
Minimum detectable relative lift
10.99%
Detectable conversion rate
A smaller MDE is not automatically better: it requires more traffic. This uses the same two-proportion, two-tailed formula as the sample size calculator, inverted by binary search.
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