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GPT-5.3-Codex is here. It advances both frontier coding performance and professional knowledge capabilities together in a single model. https://t.co/mAyt3snLY9
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View on XGPT-5.3-Codex Unifies Coding and Reasoning With Near-Double Computer-Use Accuracy
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OpenAI released GPT-5.3-Codex, combining the coding capabilities of GPT-5.2-Codex with GPT-5.2's broader reasoning into one model. It achieves new highs on SWE-Bench Pro and Terminal-Bench 2.0 while using fewer tokens than any prior model, and scores 64.7% on OSWorld-Verified — up from 38.2% — making it OpenAI's strongest computer-use model for vision-based tasks across Ubuntu, Windows, and macOS.
The model also shares progress and explains decisions as it works, letting you steer tasks in real time instead of waiting for a final output. OpenAI notes it's the first model that was instrumental in creating itself — the team used early versions to debug training and diagnose evaluations. It's also the first model classified as High capability for cybersecurity under OpenAI's Preparedness Framework.
GPT-5.3-Codex is available on all paid ChatGPT plans across the Codex app, CLI, IDE extension, and web, with API access coming soon.
