📄 Article
Free
Intermediate
Why we picked it The most rigorous free explainer on running valid tests without fooling yourself with noise - essential reading before you're tempted to call a test 'significant' after 40 conversions.
What Is A/B Testing? The Complete Guide: From Beginner to Pro
From cxl.com by CXL
- Calculate sample size ahead of time rather than eyeballing a dashboard - a rough rule of thumb is 350+ conversions per variation before trusting a result.
- Conversion research, not guessing, is what generates test ideas actually worth running.
- Test the biggest friction point you can find, not the ten-minute button-color change.