confidence level in a/b testing landing pages

Confidence Level


The probability that the winning variation of your A/B test had more conversions for reasons other than chance. Before declaring a winner, you want a confidence level of 95% or more, as well as a sufficient number of conversions.

Conversion expert Michael Aagaard explains why confidence level is a necessary, but not sufficient factor in determining a valid test.
“Running an A/B test without thinking of statistical confidence is worse than not running a test at all.” — @peeplaja
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  1. A/B Testing Significance Calculator
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  3. 10 Things To Know About Confidence Intervals