Keywords · Ops · Product · Updated 2026-07-21

What is Experimentation / A/B Testing?

Short answer: The practice of testing a change against a control group to measure its true causal effect on a metric before rolling it out broadly.

Definition

The practice of testing a change against a control group to measure its true causal effect on a metric before rolling it out broadly.

Why it matters for growth

Experimentation replaces opinion-driven product decisions with evidence, preventing teams from shipping changes that feel right but actually hurt key metrics.

Example

A team splits new signups 50/50 between two onboarding flows and measures which one produces a higher 7-day retention rate.

FAQ

What is Experimentation / A/B Testing?
The practice of testing a change against a control group to measure its true causal effect on a metric before rolling it out broadly.
Why does Experimentation / A/B Testing matter for growth?
Experimentation replaces opinion-driven product decisions with evidence, preventing teams from shipping changes that feel right but actually hurt key metrics.
What is an example of Experimentation / A/B Testing?
A team splits new signups 50/50 between two onboarding flows and measures which one produces a higher 7-day retention rate.
What is Experimentation / A/B Testing? Definition and growth use · Cofounderbase