AI-generated ads deliver human-level CTR in live campaigns: Study

New Delhi: AI-generated advertising creatives can perform on par with, and in some cases outperform, human-made ads in real-world performance marketing environments, according to a large-scale academic study led by Columbia University and conducted in collaboration with Taboola.

The findings are part of a research paper titled AI in Disguise – Quasi-Experimental Analysis of a Large-Scale Deployment of AI-Generated Display Ads, authored by researchers from Columbia University, Harvard University, the Technical University of Munich, and Carnegie Mellon University, using live campaign data from Taboola’s performance marketing platform, Realize.

Unlike lab-based experiments or surveys, the study analysed real market behaviour across more than 300,000 display ads, over 500 million impressions, and approximately three million clicks. The ads spanned multiple sectors including personal finance, food and drink, and education, making it one of the largest real-world evaluations of generative AI in advertising to date.

To ensure a fair comparison, researchers used a “sibling ads” methodology, matching AI-generated and human-made creatives from the same advertiser, running on the same day, for the same campaign, with identical objectives and landing pages. This approach isolated the impact of creative generation itself, eliminating external performance variables.

Across the full dataset, AI-generated ads delivered click-through rates (CTR) that were statistically equivalent to human-made ads. In some cases, AI creatives showed marginally higher CTRs, demonstrating that speed and efficiency from AI do not come at the cost of effectiveness.

When stricter controls were applied within identical campaign environments, AI and human creatives continued to show equivalent performance, reinforcing that AI-generated ads can scale without compromising results. Importantly, the study also found no evidence that AI-driven creatives led to low-quality or curiosity-driven clicks. Conversion rates remained stable, addressing a key concern among advertisers about downstream performance.

A critical insight from the research is that consumer perception matters more than whether an ad is actually created by AI or a human. Ads perceived as AI-generated consistently underperformed, even when those ads were in fact human-made. Conversely, AI-generated ads that were perceived as human-made delivered the highest CTRs across all categories, outperforming both clearly human and clearly AI-looking creatives.

The perception study revealed that nearly half of AI-generated ads were judged by users to be human-made, and consumers often struggled to accurately identify an ad’s origin. This highlights that visual cues and creative execution, rather than disclosure or production method, shape engagement outcomes.

The strongest driver of “human-ness” and engagement was the presence of large, clear human faces. Human faces emerged as the single most influential factor in making ads feel authentic and trustworthy, significantly boosting CTR. Notably, AI-generated ads created using Taboola’s GenAI Ad Maker were more likely to include prominent human faces than human-made ads, reflecting the tool’s built-in adherence to long-standing creative best practices.

By contrast, ads that appeared overly artificial were penalised by users. Common signals associated with AI perception included highly stylised or over-polished visuals, heavy colour saturation, and strong symmetry. These cues reduced engagement regardless of whether the ad was actually created by AI or by a human designer.

The study also found that industry context still plays a role. Strong AI-driven performance gains were observed in categories such as personal finance and food and drink, while results were more muted in education. This suggests that while generative AI is a powerful creative tool, its impact varies by sector and should be deployed strategically.

Overall, the research concludes that generative AI is reshaping how advertising creative is produced at scale. When aligned with proven, human-centred creative principles, such as authenticity and the use of real human imagery, AI-generated ads can match or exceed traditional creative benchmarks without sacrificing conversion quality.

For advertisers, the takeaway is clear: AI offers speed, efficiency, and scale, but success depends on avoiding obvious artificial cues and focusing on what audiences respond to most, ads that feel human, relatable, and real.