A/B Test
You might say
Do not choose between these sign-up pages by taste. Randomly split users and compare the same metric.
An experiment that randomly assigns eligible users to variants and compares them using predefined metricsEligible new visitors can be randomly shown one of two sign-up pages during the same period, then compared on completion rate. A before-and-after comparison or changing metrics mid-test does not provide the same causal evidence.
Also calledA/B TestingSplit Test
Further reading