A/B Testing

Splits a randomized audience between two variants that differ in one element, then compares outcomes to decide which performs better.

Both platforms provide built-in split tests that divide the audience so people see only one cell, avoiding the overlap you get from simply running two ad sets side by side. Use it for creative, landing pages, audiences, or bid strategy, one variable at a time. The usual failure is calling a winner on a handful of conversions, where the observed gap is well inside normal variance.