The big headlines on this release are efficiency, with OpenAI reporting that GPT-5.4 uses far fewer tokens (47% fewer on some tasks) than its predecessors).

The ChatGPT Thinking version features a new interaction style, where the model first displays an upfront plan of its reasoning process.

OpenAI released GPT-5.4 in ChatGPT (as GPT-5.4 Thinking), the API, and Codex, calling it its most capable and efficient ...

ChatGPT is now using its 5.4 Thinking model for deeper reasoning, and it's even better at handling "professional work." ...

Excel table formulas shift from cell positions to named columns with #All-style tags, keeping calculations readable when layouts change.

OpenAI launches ChatGPT for Excel powered by GPT-5.4, enabling users to build, update, and analyze spreadsheet models using plain language.

For agents, the value is clearer still: structured JSON output, reusable commands and built-in skills that let models interact with Workspace data and actions without a custom integration layer.

OpenAI has announced ChatGPT for Excel alongside new financial app integrations, positioning its latest model, GPT-5.4, at the centre of ...