// definition

A/B Testing

A/B testing (split testing) is the practice of showing two variants — A and B — to different segments of your audience at the same time and measuring which produces a better result, such as more signups. The winner is decided by data, ideally with enough sample size to be statistically significant.

Why it matters for developers

A/B testing replaces opinions with evidence. For developers, it is the scientific method applied to marketing: form a hypothesis, run the experiment, keep what works.