Similarweb shows who's winning the ad auction inside ChatGPT and AI Mode
Unlike Meta, Google, or TikTok, AI surfaces have no public ad transparency layer, so advertisers have been bidding blind. Similarweb's new AI Ads dataset finally opens that up: which creatives and landing pages win placement, in which market, plus share of voice. The catch that makes it credible: it's built from real anonymized user sessions, not synthetic prompts. Already 26% of ChatGPT replies and nearly 30% of ad-eligible AI Mode queries carry sponsored ads, so the stakes are live now.