Designing an A/B Test

Summary

Defining the change, the hypothesis, the metric, and the split before launching — a well-designed test answers a clean question; a poorly designed one produces an ambiguous result nobody can act on.

• 1Design a full A/B test plan for a real feature idea: hypothesis, metric, and split.
• 2Learn to define your primary metric and 1-2 guardrail metrics upfront.
• 3Practice stating what result would make you call the test a win, loss, or inconclusive.