Key Takeaways:
The AI chatbot market is no longer a one-player game. ChatGPT's share of monthly active users fell below 50 percent for the first time in March, down from 81 percent a year earlier, as rivals Claude and Gemini captured a growing slice of the consumer AI market, according to Sensor Tower's State of AI report.
"Users remain willing to try alternative AI assistants, and the competitive window is widening," Sensor Tower analysts wrote in the report, which tracked iOS and Android app data through May 2026.
ChatGPT's iOS and Android apps reached 1 billion monthly active users in May, making it the fastest consumer app to hit that milestone. But its market share erosion tells a different story. Anthropic's Claude saw its global share double to 10 percent in April from 5.1 percent in February, helped by a surge of uninstalls of the ChatGPT app after OpenAI signed a contract with the Pentagon in March. ChatGPT uninstall rates peaked at 202 percent above normal levels that month, Sensor Tower data shows.
The monetization gap is even starker. Claude converts 13 percent of its iOS users into paying subscribers at $20 per month, compared with ChatGPT's 8 percent conversion on its $8-per-month plan. That gives Claude an average revenue of $2.76 per user, 1.6 times ChatGPT's $1.74. Anthropic does not offer a low-cost tier — its base plan starts at $20 — while OpenAI's cheapest "Go" tier costs $8 and Google recently cut its Gemini Plus plan to $5 per month.
Why Claude earns more per user despite fewer total users
Claude's premium-only pricing model filters for higher-intent users willing to pay for advanced capabilities, while ChatGPT's tiered structure captures volume at lower price points. The strategy is working: Claude's user retention rate has climbed to 73.7 percent, narrowing the gap with ChatGPT's 86 percent. OpenAI's broader user base — which includes free-tier users who never convert — drags down its per-user revenue metrics.
Google's Gemini is the fastest-growing AI app in key markets including the US, Canada, most of the European Union, Japan and South Korea, Sensor Tower found. The price cut to $5 per month for Gemini Plus, announced earlier this month, signals Google's intent to compete on cost as the market matures.
The $4.25 billion question
Consumers are expected to spend $4.25 billion on AI apps in the first half of 2026, more than double the $1.83 billion spent in the same period last year, Sensor Tower projects. That growth is attracting new entrants and pressuring incumbents on pricing. The Wall Street Journal reported last week that OpenAI is considering major price cuts for its enterprise tools to compete with Anthropic, while Apple's upcoming Siri AI update — which runs partially on-device without a subscription — could further disrupt the consumer AI pricing model.
For investors, the takeaway is clear: the AI chatbot market is shifting from a land-grab for users to a battle over monetization and retention. OpenAI's first-mover advantage in consumer mindshare is real — 1 billion monthly users is a formidable moat — but its ability to convert that audience into revenue is being challenged by rivals with higher-yield pricing strategies. Microsoft, which has invested more than $13 billion in OpenAI, faces indirect exposure if the partnership's value erodes with OpenAI's market share. Alphabet, meanwhile, can afford to subsidize Gemini's $5 price point through its broader advertising ecosystem, a luxury Anthropic and OpenAI lack.
This article is for informational purposes only and does not constitute investment advice.
