A new NBER working paper by researchers from OpenAI, Duke University, and Harvard provides the first comprehensive analysis of how people actually use ChatGPT, drawing on data from its launch in November 2022 through July 2025. By that point, ChatGPT had been adopted by roughly 10% of the world's adult population. The study finds that early adopters were disproportionately male, but the gender gap has since narrowed dramatically, and growth rates have been higher in lower-income countries.

Using a privacy-preserving automated classification pipeline on a representative sample of conversations, the researchers find that non-work usage has grown from 53% to over 70% of all conversations, outpacing the steady growth in work-related messages. Work usage skews toward educated users in highly-paid professional occupations. The three dominant conversation topics — "Practical Guidance," "Seeking Information," and "Writing" — collectively account for nearly 80% of all conversations. Writing is particularly dominant for work tasks, underscoring chatbots' distinctive advantage over traditional search engines in generating digital outputs. Notably, computer programming and self-expression represent relatively small shares of overall use, challenging common assumptions about LLM chatbot adoption patterns.

The paper concludes that ChatGPT's primary economic value lies in decision support, which is especially impactful in knowledge-intensive jobs. The study was conducted with Harvard IRB approval, though several authors are OpenAI employees, a disclosed affiliation.