The Next Web reports that ChatGPT’s billion monthly users figure reflects mobile app installs only, not web traffic or API access — a methodological detail that matters when sizing the milestone. Even on that narrower measure, the number is staggering: reached in roughly 3.5 years since the November 2022 launch, faster than any app in history, eclipsing Google Maps’ previous record of around five years.
| Metric | Value |
|---|---|
| ChatGPT mobile MAUs (May 2026) | 1 billion |
| ChatGPT MAU growth, year-on-year | 62% |
| Claude global mobile MAUs (Q2 2026) | ~56 million |
| Claude MAU growth, year-on-year | 640% |
| Meta AI MAU growth, year-on-year | 973% |
| ChatGPT uninstall spike (Feb. 28) | +295% day-on-day |
The public mood around artificial intelligence has curdled noticeably. College graduates jeered AI mentions at commencement speeches. Anthropic called for a global pause in AI development on Friday, warning that systems capable of building their own successors require far more rigorous oversight. Pope Leo, in a May 25 letter, raised concerns about inequality and safety. None of it has slowed installs.
What ChatGPT’s Billion Monthly Users Actually Measure
The ChatGPT billion monthly users count, sourced from Sensor Tower, captures mobile app sessions in May 2026. OpenAI itself said in February that ChatGPT had more than 900 million weekly active users across web and mobile combined, and claimed six times the monthly sessions of the next-largest AI platform. The Sensor Tower mobile figure and OpenAI’s own cross-platform number are measuring different things — neither is wrong, but the gap between them signals just how much of ChatGPT’s traffic still flows through browsers rather than apps.
Competitors are growing faster off a smaller base. Sensor Tower estimates Claude at roughly 56 million global mobile MAUs as of Q2 2026, a fraction of ChatGPT’s total but expanding at 640% year on year. Meta AI posted 973% growth over the same period. ChatGPT’s own 62% annual gain is large in absolute terms. In relative terms, the gap is closing.
The Pentagon Moment and Claude’s Cannibalization Effect
Sentiment-driven switching is real, even if it is episodic. When OpenAI announced a deal to deploy its models on classified Pentagon networks, ChatGPT uninstalls surged 295% day-on-day on February 28. Claude jumped to the top of the U.S. App Store that same weekend, outpacing ChatGPT by downloads for the first time, after Anthropic publicly declined Pentagon involvement.
The effect lingered in usage data. Sensor Tower found that U.S. users who installed Claude during Q1 2026 spent 5% less time on ChatGPT a month later, measured against their own prior eight-month average. Modest cannibalization, but the direction is clear.
Anthropic’s relationship with the Pentagon subsequently deteriorated further. According to Anthropic’s IPO S-1 filing, the company released a model called Claude Mythos Preview with advanced cybersecurity capabilities, and its models were later blacklisted by the Pentagon after negotiations between the two sides collapsed. The episode has become a recurring reference point for users weighing the ethics of which platform to support.
IPO Wave Adds a New Layer of Scrutiny
Both companies are now navigating public listings. OpenAI submitted its IPO filing Monday. Anthropic filed its prospectus with the SEC a week earlier. The S-1 disclosures add financial transparency that user-count figures alone cannot supply — including Anthropic’s compute arrangement with SpaceX, which carries a price tag of $1.25 billion per month through May 2029, per the prospectus. That cost structure raises questions about the path to profitability even as user growth accelerates.
The AI IPO pipeline also includes SpaceX, which filed publicly on May 20 targeting Nasdaq under ticker SPCX. The cluster of listings means the AI sector’s usage metrics will soon be stress-tested against revenue and margin figures that venture-backed opacity previously obscured.
Sensor Tower’s Abe Yousef put it plainly: while negative sentiment toward AI is growing, consumers keep using and relying on these platforms. A BCG poll of roughly 12,000 frontline workers, released June 3, showed 74% regularly use AI, up 23 percentage points year on year. More than 40% of regular users reported saving the equivalent of a full workday each week.
The key test for the ChatGPT billion monthly users story is whether that base holds as Claude and Meta AI sharpen their models. OpenAI’s 62% growth rate still looks solid. But the next Sensor Tower read, after both S-1 filings generate fresh headlines, will show whether sentiment-driven switching is a transient blip or the start of a structural shift.
