If you report ChatGPT as a traffic channel, OpenAI just gave you a reason to spend more. The company says ChatGPT search volume is now about a fifth of Google's, and it defines a search as any question that sends ChatGPT to the web.
An independent study points elsewhere. In 12 months of GA4 data from 100 sites, Marie Haynes found ChatGPT sessions equaled 0.62 percent of Google organic sessions. If both numbers hold, 0.62 divided by 20 suggests each ChatGPT search sends roughly 1/32 of the visits a Google search does. That is my arithmetic across two unrelated datasets, a rough estimate.
I read a fifth of Google as demand your analytics cannot show you. I would not report it as a traffic source a fifth the size of Google.
Alex Kantrowitz of Big Technology broke the claim on X on November 2, 2026, and his full interview with OpenAI followed on November 3.
Kantrowitz wrote that OpenAI says it has internal data showing ChatGPT search volume is "already about a fifth of Google's," and that the company believes its share is growing quickly. OpenAI has not published the data or the method. The interview adds a definition from the company's side. Adam Fry, who leads ChatGPT's consumer product, told Kantrowitz at an OpenAI-hosted dinner in New York that ChatGPT's volume of search-like queries is roughly one-fifth of Google's.
Kantrowitz asked whether each prompt in a 20-prompt chat counts. Fry answered: "Every time you ask a question and go search the web, that's a search."
That tells us what OpenAI counts. It does not tell us how its count lines up with Google's, because OpenAI has not said whether Google's side was measured the same way.
Why the two numbers clash
TechCrunch reported in July 2025 that OpenAI told Axios ChatGPT received 2.5 billion prompts a day. In the same piece, TechCrunch said Alphabet had revealed 5 trillion Google queries a year. That averages to just under 14 billion a day, and a fifth of it is a little under 3 billion. ChatGPT has grown since then. Fry told Kantrowitz it went from 1 billion to 1.2 billion weekly users in two months, and Gradually AI reports OpenAI gave the 1.2 billion figure on October 5.
Haynes looked at 12 months of GA4 data from 100 sites with more than 145 million sessions. In her words: "In this dataset, sessions from ChatGPT amounted to just 0.62% of the volume driven by Google Organic." Adding all LLMs combined lifted it to 0.73 percent. Her post argues that GEO is a distraction, and her consultancy sells Google-focused diagnostics. Her figures count website sessions, not searches, and 100 sites is a sample that does not stand in for the whole web. GA4 can also file some ChatGPT visits as direct when the referrer is dropped, which would push her number lower than the real one.
The two datasets do not measure the same thing, and I would not call either one wrong. They do pull in opposite directions, and the gap between them is what a marketer has to explain to a client.
What could explain the gap
I see three possibilities, and the data here cannot choose between them. ChatGPT may answer many lookups inside the chat and the person never visits a site. OpenAI's count may include several web searches for a single task. And some visits may be arriving without a referrer that GA4 can read. Any one of these would fit the numbers, and more than one probably applies.
What I keep coming back to is that a ChatGPT search and a visit to your site are separate events. Retrieval and citation are not the same thing either, and a page can be read without being linked. I think a person who sees your brand recommended in an answer is more likely to search for you by name a few seconds later than to click the citation. If that is right, the payoff lands in branded search, not in ChatGPT sessions. That is my hypothesis, and nothing in either dataset proves it.
So I would keep ChatGPT out of the traffic column of your report for now. Track it as demand and as brand mentions, and watch branded search for the lift. The number I would want from OpenAI is how many of those searches end with someone landing on a site, and so far nobody outside the company can see it.
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