A/B Test Significance Calculator

Know if your winner is actually winning.

A/B Test Significance Calculator runs a textbook two-proportion z-test on your test results instead of eyeballing a percentage difference. It computes each variant's conversion rate, the relative uplift of B versus A, the pooled proportion, the standard error, and the resulting z-score — then converts that z-score into a real two-tailed p-value using a standard normal CDF approximation, so the significant/not-significant verdict is backed by actual statistics instead of a gut feeling.

• →Computes conversion rate and relative uplift % for both variants instantly
• →Runs a proper two-proportion z-test with pooled standard error, not a rough estimate
• →Converts the z-score to an accurate two-tailed p-value using a normal CDF approximation
• →Clear significant / not-significant verdict at the standard 95% confidence threshold
• →Shows every intermediate number — pooled proportion, standard error, z-score — for full transparency
• →Watermarked by Cikal Studio Labs · Works on any device, no install required