Google Gemini Starts Tagging Outbound Links With UTMs
Google has begun appending UTM parameters to links Gemini sends out, giving site owners a way to attribute visits from the assistant that previously landed in analytics as direct traffic. The change was spotted by users on Reddit within the past day and appears to work in a similar way to ChatGPT's tagging.
Referrer data from Gemini was already unreliable. It mostly survives on desktop web, passes through from the mobile app only about 9 percent of the time, and is stripped entirely when Gemini is invoked through the Android assistant. A UTM survives the in-app webview and shows up in raw server logs, so a large share of Gemini traffic that GA4 filed under direct can now be tied back to the platform.
For brands and agencies tracking AI referrals, the practical effect is that Gemini can be segmented and compared against ChatGPT and traditional search on real numbers rather than estimates. That makes it easier to justify spending on AI channels.
Google has not documented the behaviour, so it is not yet clear which Gemini answers trigger the parameters. ChatGPT applies UTMs only to links in answers grounded in web sources, not to answers drawn from training data.
Reported by Search Engine Journal ↗
Topics: Gemini, Measurement, ChatGPT