No app in history has grown this fast. ChatGPT reached 1 billion monthly active users in May 2026, roughly three years after its November 2022 launch. According to Sensor Tower, a leading market intelligence firm, no other app in history has crossed that threshold as quickly.
This milestone is not just a number. It is a signal that artificial intelligence has moved from an experiment into the daily lives of one in every eight people on Earth. To understand why this matters, consider the scale. One billion monthly users means that ChatGPT is now used more frequently than many countries have people. Furthermore, the growth is not slowing down — ChatGPT recorded 5.51 billion website visits in April 2026 alone.
Here are some details:
Anthropic’s Claude grew its monthly active user base by 640% year over year in the second quarter of 2026. Meanwhile, ChatGPT grew by 62% over the same period. Both figures are strong. However, Claude’s growth rate is more than ten times faster.
Moreover, the data suggests that Claude is already pulling users away from ChatGPT. Sensor Tower found that US-based ChatGPT users who installed Claude in early 2026 spent roughly 5% less time on ChatGPT one month later. That is a small number. But in a market with billions of users, even small shifts carry enormous weight.
How ChatGPT Grew So Fast:
1. November 2022 — ChatGPT Launches
OpenAI releases ChatGPT as a free research preview. It gains 1 million users in just 5 days.
2. 2023 — Mainstream Explosion
ChatGPT becomes the fastest app to reach 100 million users. OpenAI launches ChatGPT Plus and API access.
3. 2024 — Revenue Triples
OpenAI’s revenue reaches approximately $3.7 billion, more than tripling from the prior year.
4. February 2026 — 900 Million Weekly Users
OpenAI announces 900 million weekly active users and 50 million paying subscribers.
5. May 2026 — 1 Billion Monthly Users
ChatGPT becomes the first app in history to reach 1 billion monthly active users in under three years.