Introducing GPT-5.4 in Codex

GPT-5.4 is now available in Codex as OpenAI’s most capable and efficient frontier model for professional work.

It combines recent advances in reasoning, coding, and agentic workflows in one model, and it’s the recommended choice for most Codex tasks.

In Codex, GPT-5.4 is the first general-purpose model with native computer-use capabilities. GPT-5.4 in Codex includes experimental support for the 1M context window. It supports complex workflows across applications and long-horizon tasks, with stronger tool use and tool search that help agents find and use the right tools more efficiently.

GPT-5.4 is available everywhere you can use Codex: the Codex app, the CLI, the IDE extension, and Codex Cloud on the web. GPT-5.4 is also available in the API.

To switch to GPT-5.4:

• In the CLI, start a new thread with:

  codex --model gpt-5.4

  Or use /model during a session.
• In the IDE extension, choose GPT-5.4 from the model selector in the composer.
• In the Codex app, choose GPT-5.4 from the model selector in the composer.

If you don’t see GPT-5.4 yet, update the CLI, IDE extension, or Codex app to the latest version.