OpenAI’s flagship product ChatGPT is showing signs of slowing momentum, even as Google Gemini continues to close the gap, according to fresh traffic and market-share data from Similarweb.
Traffic trends show cooling growth
Data analysed by Similarweb indicates that ChatGPT’s average daily visits have declined sharply over the past six weeks. Traffic fell by about 22%, with the seven-day average dropping from roughly 203 million visits to around 158 million by early January. In contrast, Google Gemini’s traffic remained relatively stable during the same period, clocking around 55–60 million daily visits.
Market share gap continues to shrink
The slowdown in traffic has translated into a visible shift in market share. As of January 2, 2026, ChatGPT accounted for about 64.5% of the global generative AI market, down from nearly 68% in December 2025 and a steep fall from around 86% a year earlier. Gemini’s growth has been notable, expanding its share from 5.7% in January 2025 to approximately 21.5% now.
Smaller platforms are also gaining incremental traction. Grok has crossed the 3% mark and is closing in on DeepSeek at around 3.7%. Perplexity and Claude remain steady at about 2% each, while Microsoft’s Copilot continues to trail at roughly 1.1%.
Engagement patterns favour Gemini
While ChatGPT still leads in overall traffic, user engagement metrics suggest Gemini may be catching up in quality of usage. Average session duration on Gemini stands at 7 minutes and 20 seconds, compared with 6 minutes and 32 seconds on ChatGPT. Page views per visit are also higher on Gemini, at 4.3 versus ChatGPT’s 3.8.
According to Similarweb estimates, Gemini cannibalised roughly 31–33% of ChatGPT’s traffic in early December, rising to nearly 39–40% by month-end, underscoring intensifying competition in the generative AI landscape.
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