OpenAI reports that ChatGPT has exploded from a niche tool for AI researchers to over 700 million weekly active users in just two and a half years. More than a quarter of U.S. workers now use it on the job, with adoption highest among younger employees and those with postgraduate degrees. The tool skipped traditional enterprise rollout—no costly training or slow onboarding—because people brought it from their personal lives into their jobs. Scientists, marketers, and operators are using it daily for everything from debugging code to brainstorming campaigns. The report combines anonymized usage data with third-party studies, noting that AI in the workplace has gone mainstream fast, though adoption varies by industry. Why it matters: This bottom-up, consumer-driven adoption pattern is reshaping enterprise tech, proving that AI tools can bypass legacy sales cycles and embed directly into daily workflows—changing how work gets done fundamentally.