https://cdn.openai.com/pdf/5d1e1489-21c0-43e4-9d42-f87efdbf0082/the-shift-to-agentic-ai-evidence-from-codex.pdf
OpenAI's Codex active users grew more than 5X the first half of 2026, and the fastest growth came outside the original developer audience.
Usage exploded (per OpenAI's new research report):
- Longer tasks are becoming the new normal. By May 2026, 80.6% of sampled individual users had asked Codex to do work that would take a human more than 30 minutes. 70.2% had asked for tasks over 1 hour, and 25.6% had requested jobs above 8 hours.
- AI agents are not staying with developers. Engineers adopted Codex first, but Legal, Finance, Recruiting, and other non-technical teams quickly joined in. Within OpenAI, Codex now generates 99.8% of weekly output tokens.
- Non-developer adoption is rising fastest. Since August 2025, non-developer Codex usage grew about 137x among individual users and 189x among organizational users.
- Agents are expanding what workers can take on. Non-technical employees are using Codex for automation, data transformation, debugging, tooling, analysis, and technical tasks beyond their usual jobs.









