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CTA Button A/B Test Calculator
See if your A/B test is actually statistically significant.
Variant A (control)
Variant B (test)
Result
Rate A
4.00%
Rate B
4.90%
Relative lift
22.5%
Confidence
97.1%
Statistically significant
About this tool
Enter visitors and conversions for control (A) and test (B) variants to get conversion rates, relative lift, and statistical confidence via a two-proportion z-test. Includes a 95% significance flag.
What it does
- •Two-proportion z-test
- •Relative lift %
- •95% significance flag
- •Confidence percentage
Use cases
- ★CTA button tests
- ★Headline experiments
- ★Pricing page tests
FAQ
What confidence should I aim for?
95% is the standard for shipping a change. Below that, keep running or design a bigger test.
Does it handle multivariate tests?
No — this is a two-variant (A/B) calculator. Split multi-variant tests into pairwise comparisons.