A/B Test Statistical Significance Calculator

This calculator helps you with two critical phases of A/B testing:

Planning your test - Before you start, use the "Plan Your Test" tab to figure out how many visitors you need and how long your test should run. Enter your current conversion rate, the minimum improvement you want to detect, and your daily traffic. The calculator will tell you exactly how long to run your test to get reliable results.

Analyzing your results - Once your test is complete, switch to the "Analyze Results" tab. Enter the visitors and conversions for your control and variant(s). The calculator will tell you whether your results are statistically significant - meaning the difference is real, not just random chance.

Choosing your metric - Unlike most calculators, this tool supports three ecommerce metrics:

• Conversion Rate: The percentage of visitors who convert (most common)
• Average Order Value (AOV): The average amount per order (useful when testing pricing or upsells)
• Revenue per Visitor (RPV): Revenue divided by all visitors (the most holistic metric)

Understanding the methodology - You can toggle between Frequentist and Bayesian analysis. Frequentist is the traditional approach that gives you a p-value. Bayesian gives you the probability that one variant actually beats another - many find this more intuitive for business decisions.

Every result includes a plain-English explanation so you don't need a statistics degree to understand what's going on.