| Active panelists | All | Share of the panel who sent at least one prompt during a period | Panelists in the panel or group |
| First recorded ChatGPT use | First prompt recorded, No prompt yet recorded | Cumulative share of the panel whose first prompt is on or before the end of a period, and its complement | Panelists in the panel |
| Panelists by days active | Monthly 1 day, 2-5 days, 6-10 days, 11-20 days, 21+ days. Weekly 1 day, 2 days, 3 days, 4 days, 5-7 days | Share of a period’s active panelists in the band | Active panelists in the band |
| Messages per active panelist | Median, Mean | Prompts plus replies per active panelist in a period | Active panelists in the base |
| Prompts per conversation | Median, Mean | Prompts per conversation active in a period | Conversations active in a period |
| Most-used model | GPT-3.5, GPT-4, GPT-4.1, GPT-4.1 mini, GPT-4.5, GPT-4o, GPT-4o mini, o1, o1-mini, o3, o3-mini, o4-mini, GPT-5, GPT-5.1, GPT-5.2, GPT-5 mini, GPT-5.3, GPT-5.3 mini, GPT-5.4 (incl. mini), GPT-5.5, GPT-5.5 mini, GPT-5.6 (incl. mini), Other | Share of conversations whose replies came mostly from the model | Conversations with at least one recorded reply model |
| Tool use | Image generation only, Web search only, File search only, Memory only, Canvas only, Other tools only, Multiple tools, No tools | Share of conversations active in a period that used that set of tool families | Conversations active in a period |
| Any tool use | All | Share of conversations active in a period that used at least one tool. The complement of “No tools” | Conversations active in a period |
| Reasoning model use | All | Share of conversations in which more than half of replies came from a reasoning model | Conversations with at least one recorded model reply |
