OpenAI has officially announced its groundbreaking new AI model, OpenAI GPT-5.3-Codex, set to transform the world of programming. Described as the company’s most capable “agent” model to date, this new version goes beyond simply writing code to manage nearly the entire software development lifecycle. The release coincides with Anthropic’s launch of its powerful general-purpose model, Opus 4.6, setting the stage for intense competition in the AI industry.
What’s New with OpenAI GPT-5.3-Codex?
Labeled as a “frontier model” by OpenAI, GPT-5.3-Codex operates 25% faster than its predecessors. This significant speed boost allows the model to handle much longer and more complex tasks effectively. Astute tech observers will note that the current popular version is GPT-5.2, and a general GPT-5.3 has not yet been announced. This specialized release is seen as a strong indicator that a broader GPT-5.3 model may be introduced very soon.
GPT-5.3-Codex is now available in Codex.
You can just build things.https://t.co/dyBiIQXGx1
— OpenAI (@OpenAI) February 5, 2026
Perhaps the most remarkable feature of the new model is that it contributed to its own development. The Codex team reported that the model actively debugged its own training process, managed deployment procedures, and analyzed test results. Consequently, OpenAI emphasizes that this transforms the tool from a simple code writer into a comprehensive assistant capable of performing nearly any task a developer would at their computer.
Beyond Coding: A Tool for the Entire Team
GPT-5.3-Codex offers a wide array of capabilities that extend beyond developers to assist designers and product managers. In addition to debugging, deployment, monitoring, and user research, it can also create presentation files and spreadsheets. The model can be redirected mid-task without losing context, maintaining continuous interaction with the user.
On the performance side, the model can execute operations that last for more than a day. During its testing phase, OpenAI successfully developed two different web-based games using millions of tokens. Furthermore, its ability to understand user intent has been substantially improved. Even with vague commands like “make me something cool,” it now produces far more functional and logical results with sensible defaults.
Additionally, OpenAI makes bold claims about security, stating this is the first model classified as “highly capable” for cybersecurity tasks. Trained to detect software vulnerabilities, its release is accompanied by a $10 million cybersecurity research fund. The model is currently available to users on paid ChatGPT plans, while free users will continue to use GPT-5.2-Codex for now.
So, what are your thoughts on the new GPT-5.3-Codex? Share your opinions with us in the comments!
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