A/B Testing Answers

All Answers

How Many Visitors Do I Need for an A/B Test?

For 5% baseline and 20% MDE at 95% confidence with 80% power, you need 3,623 visitors per variant (7,246 total). Sample size calculator and formula explained.

How Long Should I Run My A/B Test?

At 1,000 daily visitors with 5% conversion: run 7-8 days to detect a 20% lift. Never stop early because it looks significant.

Is My A/B Test Statistically Significant?

Check if your A/B test results are statistically significant. Example: 1,000 visitors with 50 vs 65 conversions gives p=0.108 -- not significant at alpha 0.05.

Try the Calculator

Use the ABWex A/B Test Calculator for both frequentist and Bayesian analysis with revenue impact projections and sample size planning.