ChatGPT’s global market share among AI assistants has fallen below 50% for the first time since its release, dropping to 46.4% by the end of May as users increasingly migrate to competitors including Google’s Gemini and Anthropic’s Claude, according to Sensor Tower’s State of AI Report 2026. The chatbot held over 50% market share as recently as January.
OpenAI’s chatbot remains the most popular AI assistant worldwide by a wide margin, with over 1.1 billion monthly users, having become the fastest app ever to reach 1 billion monthly users. Gemini ranks second with 662 million monthly users and 27.7% market share, while Claude holds 245 million monthly users and 10.3% share. Other assistants including Grok, Perplexity, DeepSeek, and Meta AI each hold less than 5% of the market.
Until January, ChatGPT commanded over 50% market share, but by May’s end, it had fallen to 46.4% thanks to the rise of Gemini (27.7%) and Claude (10.3%). Other assistants, including Grok, Perplexity, DeepSeek, and Meta AI, have less than 5% market share.
Research found users increasingly willing to switch between assistants, with specific events accelerating that behavior. OpenAI’s February deal with the US Department of Defense triggered a measurable spike in uninstalls, suggesting brand trust and values alignment influence user choice beyond raw features. Gemini’s momentum stems largely from its integration across Google’s broader product ecosystem, while Claude has built a strong reputation for productivity use cases and is closing in on ChatGPT’s user retention rate.
People are on pace to download nearly 2.3 billion AI apps in the first half of 2026 and spend over $4.2 billion on them, more than double the $1.83 billion spent in the same period of 2025, even as both download and spending growth rates decelerate.
Asia recorded its first download decline of 3.3% in Q1 2026, driven by dips in China and India, and continues to trail North America and Europe in in-app spending despite leading in total downloads.
Claude stands out on monetization specifically. 13% of Anthropic’s users pay for a subscription, the highest conversion rate in the industry. Meanwhile, OpenAI has begun scaling ads inside ChatGPT since February, with an average of 17% of daily users now seeing ads by May, led by software, shopping, media, and food advertisers. As ChatGPT deepens shopping integrations, it increasingly directs referral traffic to Target, Walmart, and Costco, while Amazon, which has blocked ChatGPT’s web crawlers, has seen stagnant referral traffic in return.
