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A/B Test Statistical Significance Calculator

Calculate statistical significance (z-test) for A/B test results, visitors, conversions, declared winners.

CRO Optimizely VWO
Control (A)
Variant (B)
Borderline (90%)
94.00% confidence
A CR
4.200%
B CR
4.750%
Relative lift
+13.10%
Z-score
1.881
P-value
0.0600
Lower = stronger evidence

About this tool

Z-test for proportions. Enter visitors + conversions for control and variant, get p-value, lift, and confidence-level pass/fail.

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