GPT-5.4 mini Now Available in Codex
OpenAI has released GPT-5.4 mini as a new model option within Codex, delivering improved performance with significantly lower resource consumption. The model improves across coding, reasoning, image understanding, and tool use while maintaining a lightweight footprint.
Key Performance Improvements
- 2x faster execution compared to GPT-5 mini
- 30% token usage of GPT-5.4, allowing comparable tasks to run 3.3x longer
- Improved performance across coding, reasoning, image understanding, and tool use
Recommended Use Cases
GPT-5.4 mini is designed for:
- Codebase exploration and analysis
- Large-file code review
- Processing supporting documents
- Less reasoning-intensive subagent work
For more complex planning, coordination, and final judgment, developers should continue using GPT-5.4.
How to Use
GPT-5.4 mini is immediately available across all Codex platforms:
CLI: Start a new thread with codex --model gpt-5.4-mini or use /model during an active session
IDE Extension: Select GPT-5.4 mini from the model selector in the composer
Codex App & Web: Choose GPT-5.4 mini from the model selector in the composer
Users should update to the latest versions of the CLI, IDE extension, or Codex app if GPT-5.4 mini is not yet visible.