Google’s Gemini is giving up some of the gains it had made over the past year.
Google’s Gemini has now lost website traffic share for four consecutive months, with fresh SimilarWeb data for September 2026 showing ChatGPT extending the recovery it kicked off earlier this summer.
According to the numbers, Gemini held 26.6% of worldwide generative AI website traffic three months ago, in July. That slipped to 25.6% in August, and has now eased further to 25.0% in September. ChatGPT, over the same stretch, has moved steadily the other way — climbing from 54.3% in July to 55.6% in August and now 56.4% in September.
The trend stretches back even further. Six months ago, in April, Gemini was sitting at 26.7% of traffic share, meaning the platform has now given up nearly two full percentage points over four straight months even as the overall AI traffic pie has kept growing. ChatGPT, which stood at 53.7% in April, has added close to three points in the same period — its longest run of consecutive monthly gains since the early days of Gemini’s rise.
The scale of the swing becomes clearer zooming out a full year. In October 2025, ChatGPT commanded 71.8% of generative AI traffic to Gemini’s 13.6%. Gemini’s climb from under 14% to a peak above 27% earlier this year was one of the sharpest share gains the generative AI market has seen, eating directly into ChatGPT’s lead through the back half of 2025 and into early 2026. That climb has now reversed into a steady slide for four months running, even as Gemini’s share today, at 25.0%, remains well above where it stood a year ago.
Claude has been the more consistent story below the top two. Anthropic’s chatbot has held roughly steady in the 9-10% range for three months now — 9.6% in July, 9.3% in August, and 9.6% in September — after a sharp run-up earlier in the year that took it from 8.0% in April to its current level. That puts Claude comfortably in third place, well ahead of DeepSeek (3.4%), Grok (2.3%), Copilot (1.5%) and Perplexity (0.9%), all of which have stayed roughly flat or drifted lower over the past several months.
Put together, ChatGPT and Gemini still account for more than 81% of tracked generative AI website traffic worldwide, with Claude making up most of the remainder among the named platforms. But the direction of travel over the past four months is unambiguous: ChatGPT has been clawing back share it spent much of 2025 and early 2026 losing, while Gemini’s once-blistering ascent — the one that had analysts debating whether it would overtake ChatGPT altogether — has cooled into a prolonged retreat.
It’s worth noting, as always, that these figures capture website traffic alone. They don’t account for usage through native mobile apps, API access, or Gemini’s deep integration into Android and Google Search, all of which route significant usage away from a browser. Even so, SimilarWeb’s monthly tracker remains one of the few consistent, apples-to-apples snapshots of how the generative AI market is shifting month over month — and for the fourth month running, that snapshot points toward ChatGPT, not Gemini.