A/B testing guides

Make better experiments — and know when not to run one.

Practical guides for sample planning, low-traffic testing, pre-launch research and interpreting evidence.

Guide

A/B Testing With Low Traffic: What to Do Instead of Waiting

Learn when classic split testing is underpowered, how to estimate the traffic you need, and which pre-launch research methods can help you decide sooner.

Guide

How Long Should an A/B Test Run?

Estimate A/B test duration from baseline conversion, expected lift, traffic and statistical power instead of using arbitrary one- or two-week rules.

Guide

A/B Testing Sample Size: How Many Visitors Do You Need?

Understand baseline conversion rate, minimum detectable effect, confidence and power, then estimate the sample required per A/B test variation.

Guide

Statistical Significance in A/B Testing, Explained Practically

A practical guide to p-values, confidence, effect size and why a statistically significant A/B test is not automatically a useful business result.

Guide

Pre-Launch A/B Testing: Test Decisions Before You Have Traffic

Learn which product, positioning and creative decisions can be tested before launch and which claims still require live behavioral experiments.

Guide

Preference Testing vs. A/B Testing: Which Should You Use?

Compare preference tests and live randomized A/B experiments, including what each method can prove, when each is useful and where teams commonly confuse them.