ChatGPT’s grip on the chatbot market is loosening, and Google’s Gemini is the main beneficiary. Comscore’s AI Intelligence Report for the second quarter of 2026 shows ChatGPT holding half of the “prompt volume” across the chatbot landscape, but Google’s Gemini has risen to 30% and Anthropic’s Claude has reached 11%.
The numbers come from Comscore’s opt-in panel, which assembled a respondent base between 500,000 and 1 million users. Over the past half-year, ChatGPT’s market share fell 20%, with Gemini rising 13% and Claude up 9%.
The Numbers Behind the Slide
Tubefilter’s report applies a similar framework to LLMs as Comscore has long used for online video rankings. Among the panel cohort, the shift is clear: users are moving away from ChatGPT toward its rivals.
ChatGPT’s dominance dates back to its first few months, when it challenged traditional search engines with explosive user growth. Now, three years after its launch, consumers are finding reasons to look elsewhere for answers.
What Changed Since the Start of the Year
One major shift has reshaped the landscape since January. Answer engine optimization, or AEO, has moved from a curiosity to a preferred marketing strategy. Brands now push content to rank in chatbot results.
That shift creates noticeable differences among LLMs that used to be more interchangeable. Michael King, founder and CEO of the agency iPullRank, recommended a more targeted approach to chatbot marketing.
“Publishers should stop asking ‘how do we show up in ChatGPT’ and start asking ‘where is our audience actually asking questions, and are we showing up there,'” King told Digiday. “That means measuring visibility per assistant and weighting it by where your readers are.”
He added: “The fundamentals that get you cited are largely the same across all of them, so a durable strategy is built on those rather than on chasing whichever assistant is winning this quarter.”
The Brands Behind the Numbers
Google Gemini has gained ground through its search overviews and partnerships with influential creators like MrBeast. Meanwhile, OpenAI has shut down its video generation model Sora as Gemini’s Veo model rises.
OpenAI’s challenges have led to this move, and the timing aligns with Gemini’s ascent.
What Comes Next
Dozens of AEO tools have already popped up, which means a lot more change is likely coming to Comscore’s rankings. By the time 2027 rolls around, ChatGPT’s market share could dwindle even further.
For now, OpenAI can rest assured that it still runs the most used AI chatbot in the U.S. But the trend lines are not in its favor.
| Metric | Q2 2026 Share |
|---|---|
| ChatGPT | 50% |
| Google Gemini | 30% |
| Anthropic Claude | 11% |
The question is whether OpenAI can hold its position as more brands optimize for specific assistants. The tools exist, and the strategy has shifted. ChatGPT’s once-dominant position is no longer assumed.
The market is changing fast, and the company that started it all is now playing catch-up.
Source material: “Comscore says ChatGPT’s LLM market share is shrinking as Google Gemini advances,” Tubefilter.
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