A/B test significance
Two-proportion z-test — is the difference real or noise?
Variant A (control)
Rate: 6.00%
Variant B (test)
Rate: 7.50%
Uplift (B vs A)
+25.0%
Confidence
99.3%
p-value
0.007
Winner
B
Statistically significant. Variant B wins at 99% confidence — you can act on this result.
Aim for 95%+ confidence before calling a winner. Small samples produce big swings that don't hold up.