Turning data into results: How Meta Conversions API boosted campaign performance

Turning data into results: How Meta Conversions API boosted campaign performance

Global fashion eyewear brand Gentle Monster, faced the challenge of evolving privacy regulations and a reduced reliance on cookies, which were impacting the accuracy of their ad performance measurement.

Business challenge

As a trendsetter in the industry, Gentle Monster continuously seeks ways to refine its digital marketing strategies and better understand consumer behavior. To address the impact of changing privacy regulations and the diminishing role of cookies, the brand partnered with Jellyfish to find a data-driven solution that would deliver more precise performance insights and support their forward-thinking approach.

Jellyfish Solution

The Jellyfish Analytics team implemented a server-based Meta Conversions API (CAPI), reducing data loss from browser-transmitted pixel events and enabling high-quality data collection for improved targeting and measurement accuracy. To evaluate the impact of CAPI, the Jellyfish team carefully monitored Gentle Monster's always-on purchase campaigns, analyzing performance data before and after the CAPI implementation.

“With 3rd-party cookie restrictions limiting targeting, a solution was needed to minimize data loss and improve accuracy for high-engagement users. Implementing the server-based "Conversion API" enhanced data quality, significantly boosting ROAS.”

– Gentle Monster Marketing Manager

Impact

The adoption of Meta Conversions API helped Gentle Monster successfully navigate the challenges of a privacy-first digital landscape, driving measurable growth in advertising efficiency:

  • Improved Reporting Accuracy: The API captured a higher volume of purchase events, providing a more complete picture of campaign performance.
  • Enhanced ROAS: With better data accuracy, Gentle Monster achieved significant improvements in Return on Ad Spend (ROAS).
  • Smarter Campaign Optimization: The additional data allowed for more effective bidding strategies and sharper audience targeting.

Results

122%

Increase in Return on Ad spend

50%

Decrease in average CPA (Purchase)

52%

Additional Purchase conversion reported

Resources

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