OpenAI's advertising business reached a $1 billion revenue run rate in late August 2026, roughly 200 days after ads began on free ChatGPT accounts in February. Ads now run in more than 40 countries, and OpenAI is rolling out self-service ad buying in India, Europe, the Middle East and North Africa. The milestone lands short of the company's $2.4 billion year-end projection, leaving the pace of the remaining ramp the open question.