OpenAI has launched its new ChatGPT 5.4 with Extreme Reasoning mode for long-duration task focus. As well as a 1M-token context window ...

"In ChatGPT, GPT‑5.4 Thinking can now provide an upfront plan of its thinking, so you can adjust course mid-response while it ...

OpenAI’s new GPT-5.4 model promises stronger reasoning, better coding capabilities and the ability to handle longer, more complex tasks. To see how well those claims hold up, I tested the model with ...

This week's second new model from OpenAI is built for more complex tasks than GPT-5.3 Instant.