Eseandre Mordi
⬤ New traffic data from Similarweb reveals how people are actually using the biggest AI platforms in 2025. The numbers tell an interesting story: more ChatGPT users started checking out Gemini as the year went on. This shift kicked into higher gear after Google dropped Gemini Nano Banana at the end of August, showing that product launches really do move the needle on user behavior.
⬤ Looking at the monthly worldwide data from January through December 2025, the overlap between ChatGPT and Gemini users jumped significantly. At the start of the year, only about 9 percent of ChatGPT's primary visitors were also using Gemini. By December, that figure climbed to roughly 23 percent. The growth stayed pretty steady through the first half of the year, then picked up steam after August—meaning ChatGPT users weren't just sticking to one AI tool anymore.
⬤ Meanwhile, Gemini users were already familiar with ChatGPT from the beginning. Throughout 2025, around 40 to 50 percent of primary Gemini visitors also used ChatGPT, with the highest overlap hitting nearly 50 percent around August before easing slightly toward year-end. The real story here is that ChatGPT users started exploring Gemini more actively, especially after Google's feature updates.
⬤ Why does this matter? Because audience overlap shows how competitive the AI market is getting. When users bounce between platforms, they're comparing what each one offers as new features roll out. For Google, getting more visibility among ChatGPT's massive user base could shape how Gemini grows going forward. Beyond that, the data points to a maturing AI landscape where competition isn't just about total users—it's about how often people switch between platforms as the technology keeps advancing.
Eseandre Mordi
