A/B Test Significance Calculator

Result

Significant at 95% confidence

Conversion rate A

5%

Conversion rate B

5.7%

Relative lift (B vs A)

14%

Absolute difference

0.7%

95% CI for difference

0.076% to 1.324%

Z statistic

2.1996

Decide the sample size before the test starts; stopping as soon as results look significant inflates false positives.