Professional A/B Testing Calculators
Instant, statistically rigorous calculators for sample size, test duration, and significance — built for CRO practitioners and data scientists who run experiments properly.
Calculators
Three tools for every stage of your experiment
Most Popular
A/B Test Sample Size Calculator
Enter your baseline conversion rate and expected lift to calculate the exact sample size, estimated test duration, and a statistical power sensitivity table.
Three Variants
A/B/C Test Sample Size Calculator
Bonferroni-corrected sample size calculator for three-variant experiments. Accounts for multiple comparisons to keep your false positive rate under control.
Post-Test Analysis
Statistical Significance Calculator
Check if your test results are statistically significant. Input your observed conversions and instantly get the z-score, p-value, and observed power.
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