99% of Marketers Find Success With A/B Testing … But Can't Agree On Which Metric Best Proves That Success

A/B testing may be one of the few tactics almost every single marketer can agree on — with 99% of marketers finding at least some success with their A/B testing program, according to a recent Ascend2 survey — but that doesn’t mean everyone’s evaluation of success is the same.

In fact, according to the A/B Testing In Marketing 2025 report, there’s a near-split at the top over which metric is most important when evaluating A/B results.

“Customer retention rate (46%) and conversion rate (45%) are the two most important metrics, emphasizing the need for both long-term loyalty and immediate impact,” the report says. “Click-through rate (41%) and time on site (36%) also rank high, highlighting the importance of engagement along the customer journey, not just the final results.”

(Source: Ascend2)

As for objectives behind their experimentation, 56% of marketers said A/B testing optimizes their campaigns, 54% said it enhances the user experience, and 53% said it improves conversion rates. AI tools have helped 92% of marketers already, reducing manual effort, accelerating tests, and helping to extract insights.

“As A/B testing becomes more complex and time-sensitive, AI is proving to be a critical ally in scaling experimentation effectively,” the report says.

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