Reddit has emerged as the leading source of data for artificial intelligence (AI) models in 2025, surpassing traditional platforms such as Wikipedia, YouTube, and Google. According to data collected by Profound and cited by Reddit's CEO, the platform is the most referenced domain across all AI models, accounting for 40.1% of AI citations. This prominence is attributed to Reddit's extensive and diverse human conversations, which cover a wide range of topics from trivial to transformative, making it a valuable resource for building effective AI systems. Industry observers note that Reddit's role as a primary data source has led to increased visibility in AI search results, with platforms like ChatGPT, Perplexity, and Gemini frequently citing Reddit content. This shift positions Reddit as a surprising winner in the evolving AI-driven internet search landscape, challenging the dominance of established search engines like Google.