Epoch AI has launched the ChatGPT Usage Explorer, a public research tool built on metadata from 8.3 million messages across 660,000 conversations by 5,000 US YouGov panelists. Unlike most behavioral data on AI use, which is either self-reported or published by AI companies themselves, this dataset provides independent, message-level records spanning from ChatGPT's November 2022 launch through 2026. The explorer publishes nine metrics covering panelist activity, conversation patterns, model usage, and demographic breakdowns, all without exposing any message text.

The clearest finding is intensification: active users are steadily using ChatGPT more. The median number of monthly messages per active panelist rose from 14 in January 2023 to 36 in December 2025, and the share of panelists using ChatGPT on 21 or more days per month quadrupled from 2.6% to 10.5%. Usage is also highly concentrated — the top 10% of users sent 63% of all prompts. Interestingly, while mean conversation length grew significantly, the median conversation remained just two prompts throughout the entire period.

The authors are transparent about limitations: the dataset skews older and more educated than ChatGPT's overall user base, and is subject to survivorship bias since all panelists had to have used ChatGPT in 2026. Despite this, the panel's usage rates closely match OpenAI's own published figures, with weekly active panelists averaging 4.3 prompts per day versus OpenAI's implied 3.7. Epoch AI positions the explorer as a complement to its representative polling work and plans to further analyze heavy users and individual usage trajectories over time.