Ab Test Designer

This takes you through designing a proper A/B test with all the pieces product teams actually need: hypothesis formation, sample size calculations, variant definitions, guardrail metrics, and analysis plans. It's built around a structured framework that forces you to think through risks and decision criteria before you run anything. Use it when you're testing a feature change, optimizing conversion rates, or need data to back a product decision. The best part is it pushes you to define success upfront and calculate how long to run the test, which stops teams from either calling tests too early or letting them run forever without learning anything.