ChatGPT crossed 1 billion monthly active users in May, becoming the fastest app ever to hit that mark. It took just 3.5 years from its November 2022 launch, beating Google Maps' five-year record, according to Sensor Tower data cited by CNBC.
But the milestone tells only part of the story. OpenAI's rivals are growing at a far faster clip, and public sentiment toward AI has soured dramatically, even as usage keeps climbing.
Sensor Tower figures cited by Reuters put Meta AI's year-on-year user growth at 973% and Claude at 640%. ChatGPT managed 62% over the same stretch.
Claude's global monthly active app user count now sits at 56 million for the current quarter. The divergence traces directly to a single event. OpenAI's February agreement to deploy its models on classified Pentagon networks triggered a roughly 295% day-on-day spike in ChatGPT uninstalls, Sensor Tower data showed.
Over that same weekend, Anthropic, which distanced itself from Pentagon work, saw Claude jump to the App Store's top spot, outpacing ChatGPT in U.S. download volume for the first time.
American ChatGPT users who added Claude to their devices during the first quarter of 2026 cut their time spent on OpenAI's app by 5% within a month, relative to their prior eight-month baseline.
"While negative sentiment towards AI is undeniably growing. Consumers are increasingly using and relying on these platforms," Sensor Tower senior insights analyst Abe Yousef told CNBC. The gap between sentiment and behavior is stark. College graduates have jeered AI mentions at commencement speeches.
The Pope and Anthropic have warned about unmitigated development. A May survey documented workers opting out on ethical, environmental, or privacy grounds.
Last week Anthropic itself called for a global halt to AI development, cautioning that advances could spiral beyond human oversight.
Yet a BCG survey of roughly 12,000 frontline workers, published June 3, found nearly three-quarters now use AI regularly, a share up 23 percentage points from the prior year. Hanno Stegmann, managing director at BCG X, said the trajectory of AI adoption shows no sign of slowing.
Both OpenAI and Anthropic are now heading to public markets. OpenAI submitted a confidential S-1 filing with the Securities and Exchange Commission at an $852 billion valuation.
Anthropic filed its IPO prospectus a week earlier at $965 billion, a higher valuation than the company ChatGPT built.
