OpenAI’s ChatGPT has crossed one billion global monthly active app users, becoming the fastest application ever to reach the milestone, according to new estimates from market intelligence firm Sensor Tower.
The achievement comes nearly three years after ChatGPT’s public launch and highlights the rapid adoption of generative artificial intelligence tools by consumers, businesses, students, and professionals worldwide.
The milestone also arrives as competition in the AI industry intensifies, particularly between OpenAI and rival AI company Anthropic.
ChatGPT sets a new growth benchmark
According to Sensor Tower, ChatGPT reached one billion monthly active users in May 2026, achieving the feat faster than several of the world’s most popular digital platforms, including Google Maps, TikTok, Instagram, and YouTube.
The growth underscores how quickly AI-powered conversational tools have moved from experimental technology to mainstream products used daily by hundreds of millions of people.
Since its launch in late 2022, ChatGPT has expanded beyond text-based conversations to include image generation, voice interactions, coding assistance, web browsing capabilities, and enterprise-focused services, helping drive broader adoption across different user groups.
Also Read: OpenAI launches feature allowing users connect bank accounts to ChatGPT
Anthropic gains momentum despite OpenAI’s lead
While ChatGPT remains the dominant AI application by user numbers, Sensor Tower data suggests that Anthropic is making significant gains.
The market intelligence firm reported that users in the United States who installed Anthropic’s Claude app during the first quarter of 2026 spent 5% less time on ChatGPT one month after installing Claude compared with their average usage over the previous eight months.
The findings suggest that Claude is beginning to capture a share of user attention in a market that OpenAI has largely dominated since ChatGPT’s debut.
Sensor Tower estimated that Claude had 56 million global monthly active app users as of the second quarter of 2026. Although that figure remains far below ChatGPT’s user base, Claude’s year-over-year monthly active user growth of approximately 640% significantly outpaced ChatGPT’s 62% growth during the same period.
Also Read: The internet no longer begins with Google search
IPO plans signal maturing AI industry
The competition between the two companies is increasingly extending beyond products and users to capital markets.
Anthropic confidentially filed for a U.S. initial public offering on Monday, after the company reached a valuation of $965 billion, according to reports. OpenAI is also reportedly preparing to file for its own IPO in the coming weeks.
The potential public listings of two of the world’s leading AI companies reflect growing investor confidence in the commercial prospects of artificial intelligence and signal a new phase in the industry’s evolution.
For users and businesses globally, the rivalry between OpenAI and Anthropic could accelerate innovation, expand AI capabilities, and increase competition as both companies seek to strengthen their positions in one of the technology sector’s fastest-growing markets.
Also Read: OpenAI now lets users secure ChatGPT with hardware keys. Here’s how it works