AI chatbot market share in 2026: ChatGPT holds 46% to 80%, depending on who counts

Which AI chatbot has the biggest market share in 2026?

ChatGPT's lead is widest on StatCounter's referral count and narrowest on Sensor Tower's user count, 34 points apart. It still leads on every public share count, and every figure below links to the firm that published it.

The two counts are measuring different things. StatCounter counts the clicks a chatbot sends out to websites. Similarweb counts the visits that people make to the chatbot's own site. Perplexity is a search tool that is built around cited links, so it sends a lot of clicks for its size. Claude sends very few of them. Read together, the two counts say a Claude visit rarely ends in a click to another site. That's why the same product sits at 0.95% on one chart and 9.3% on the other.

Why do AI chatbot market share numbers disagree so much?

The numbers disagree because each firm counts a different thing: clicks out, visits in, or people. Put side by side, ChatGPT's share spans 34 points, from 46.4% to 80.48%. Claude's spans more than tenfold. The table puts every chatbot on all four public yardsticks, each column with its own date.

StatCounter measures referrals. Its May 2026 release says the data comes from over 3 billion page views a month across more than 1 million websites. It tracks six chatbots and doesn't list Meta AI or Grok. A chatbot that answers inside the chat and rarely links out scores low here, however many people use it.

Similarweb measures the visits that each chatbot's website gets from people all over the world, using its traffic panel. It doesn't count the mobile apps. That leaves out much of ChatGPT and Gemini use on phones, and it misses Meta AI, which lives inside WhatsApp, Instagram and Facebook.

Sensor Tower measures people. Its True Audience figure counts unique users across mobile apps and web, and its State of AI 2026 report says ChatGPT's share by that count fell below 50% for the first time in March 2026. MediaNama, reporting the June 2026 report, put the end of May split at 46.4% ChatGPT, 27.7% Gemini and 10.3% Claude.

Pew isn't a market share at all. It asks Americans which chatbots they use, so the column adds up to more than 100%. Most of them use more than one. It's still the only one of the four that names Meta AI and Grok next to ChatGPT.

How has AI chatbot market share changed over time?

Gemini is the big gainer on every count over the past year. On Similarweb's visit count, ChatGPT fell from 73.3% to 55.5% between August 2025 and August 2026, while Gemini doubled from 12.9% to 25.6%. Claude went from 1.9% to 9.3%. These are Similarweb's own figures from its 7 September 2026 update.

ChatGPT didn't shrink, though. It just didn't grow as fast as the rest. Similarweb's July 2026 analysis says its visit count stayed roughly flat while the whole category grew 70% in a year, to 9.5 billion visits a month on average between June 2025 and May 2026. The number of unique visitors grew by 57%, to 655 million. In Similarweb's words, "a flat leader looks like a declining one."

StatCounter's referral count tells a quieter story for ChatGPT. Its share went from 81.12% in September 2025 to 80.48% in September 2026, with a record low of 76.85% in April 2026. On that count, most of what Gemini gained came out of Perplexity, not out of ChatGPT.

Gemini first passed Perplexity in March 2026, at 8.65% against 7.07%. It slipped back behind in May, edged ahead again in June, and has pulled clear since July. Claude's referral share peaked at 3.74% in June 2026 and was back to 0.95% by September. That's a drop worth checking against next month's data before anyone quotes it as a trend.

How many users does each AI chatbot company claim?

OpenAI claims the most: 1.2 billion weekly users, stated in its DevDay recap after the 29 September 2026 keynote. Each of them counts in a different way, so you can't add up this table or rank it as a share.

The numbers in it don't line up. OpenAI counts weekly users: its DevDay recap calls them "our collective 1.2B weekly users" in a sentence about ChatGPT. Google counts monthly users of the Gemini app alone. Meta's count includes anyone who used Meta AI inside WhatsApp, Instagram, Facebook or Messenger, and Mark Zuckerberg told analysts in July 2026 that WhatsApp is the leading surface for it. He said in October 2025, "More than a billion monthly actives already use Meta AI," and Meta hasn't given a newer total.

The Grok figure comes from a securities filing, not a press statement. SpaceX's June 2026 prospectus says about 117 million of its roughly 550 million X and Grok monthly users used Grok's AI features at 31 March 2026. Google's Gemini app went from over 750 million monthly users in February 2026 to 950 million by July, per Sundar Pichai's Q2 2026 remarks.

DeepSeek and Perplexity haven't published a dated, company wide user count we could open at a primary source, so they aren't in the table. For ChatGPT's full user history, revenue and subscriber numbers, see our ChatGPT statistics page. Paid plan counts across the big chatbots are on the AI subscription statistics page.

What is AI chatbot market share by country?

ChatGPT leads chatbot referrals in all 12 large markets we pulled from StatCounter for September 2026, but its share swings from 85% in Indonesia to 36% in Russia. Gemini does best in South Korea, at 29.35%, which is 2.7 times its worldwide share.

Copilot does best in the United States, where it has 6.69%. That's close to four times what it gets worldwide (1.79%), and Japan is next at 6.21%. Indonesia is the one market where Perplexity (8%) beats Gemini (6.14%).

Two of the rows need some care. OpenAI's supported countries list doesn't include mainland China or Russia, so those rows show what people who reach the big Western chatbots anyway click on. They don't describe either country's chatbot market. StatCounter doesn't track domestic assistants, and it puts DeepSeek at just 4.9% of referrals in China.

What share of Americans use each AI chatbot?

44% of US adults say they use ChatGPT, against 24% for Gemini and 17% for Copilot, per a Pew Research Center survey run 17 to 23 February 2026. Pew found that 49% of US adults use at least one AI chatbot.

Pew's 2024 figure was 33%, but it asked that year only of people who'd heard at least a little about chatbots, so the two years aren't a clean comparison. The age gap is the bigger finding in it. Adults under 30 use ChatGPT at three times the rate of those 65 and over. Pew's chart is here.

Every figure here comes from a primary source we opened on 6 October 2026

Whizi Research opened every figure on this page at its primary source on 6 October 2026. We didn't estimate or round anything up. We took the StatCounter shares from its public chart page and from the monthly CSV export that it offers for the world and for each country. The export differs from the headline table by up to 0.03 points, so the lines chart (from the export) and the prose (from the headline table) can disagree in the last decimal.

Similarweb figures come from its own 7 September 2026 post and its July 2026 analysis. Sensor Tower's public page gives the March 2026 milestone. The end of May split and the 245 million Claude estimate are from MediaNama's June 2026 report on it, and we've labelled them that way. Company user counts come from earnings remarks, call transcripts, an SEC filing, OpenAI's DevDay recap and named reporting.

We left out three things. Figures that appear only on stats roundups, with no primary source we could open, didn't make it in. That includes a "DeepSeek 89.3% in China" figure that circulates on page one. We also skipped Similarweb's May 2026 numbers, because they exist in two versions (52.7% and 53.9% for ChatGPT). And we left out app download counts older than a year.

Prices for the same models are tracked on the LLM API pricing statistics page, and error rates on the AI hallucination statistics page.

How should you cite these AI chatbot market share figures?

The figures are free to use with a link back to this page. Please name the original measurement firm too, since each one counts something different. A plain credit line works:

Source: Whizi Research, "AI chatbot market share in 2026: ChatGPT holds 46% to 80%, depending on who counts", whizi.io/resources/ai-chatbot-market-share, updated October 2026.

We'll refresh the StatCounter and Similarweb rows each month. If you're quoting a single number, say which yardstick it is: referrals, visits or users.