"It incorporates the industry-leading coding capabilities of GPT‑5.3‑Codex⁠ while improving how the model works across tools, software environments, and professional tasks involving spreadsheets, presentations, and documents," the company said in a statement.

"The result is a model that gets complex real work done accurately, effectively, and efficiently—delivering what you asked for with less back and forth," the statement said.

In ChatGPT, GPT‑5.4 Thinking, users can now provide an upfront plan of its thinking, so that they can adjust course mid-response while it’s working, and arrive at a final output that’s more closely aligned with what you need without additional turns.

"GPT‑5.4 Thinking also improves deep web research, particularly for highly specific queries, while better maintaining context for questions that require longer thinking," the company said.

The company further said: "Together, these improvements mean higher-quality answers that arrive faster and stay relevant to the task at hand."

In Codex and the API, GPT‑5.4 is the first general-purpose model that has been released, with native, state-of-the-art computer-use capabilities, enabling agents to operate computers and carry out complex workflows across applications.

"It supports up to 1M tokens of context, allowing agents to plan, execute, and verify tasks across long horizons. GPT‑5.4 also improves how models work across large ecosystems of tools and connectors with tool search, helping agents find and use the right tools more efficiently without sacrificing intelligence. Finally, GPT‑5.4 is our most token efficient reasoning model yet, using significantly fewer tokens to solve problems when compared to GPT‑5.2—translating to reduced token usage and faster speeds," the statement said.

“GPT-5.4 is the best model we’ve ever tried. It’s now top of the leaderboard on our APEX-Agents benchmark, which measures model performance for professional services work. It excels at creating long-horizon deliverables such as slide decks, financial models, and legal analysis, delivering top performance while running faster and at a lower cost than competitive frontier models," said Brendan Foody, CEO at Mercor.