GPT-5.3-Codex

About GPT-5.3-Codex

GPT-5 represents OpenAI's next-generation flagship model, expected to deliver significant advances in AI capability across all domains. Building on GPT-4's foundation, GPT-5 aims to push the boundaries of reasoning, creativity, and multimodal understanding. The model is anticipated to feature improved factual accuracy, reduced hallucinations, and enhanced ability to follow complex instructions. GPT-5 will likely introduce new capabilities and modalities while maintaining OpenAI's focus on safety and alignment. For organizations planning future AI strategies, GPT-5 represents the next major milestone in language model development. It's expected to set new standards for AI capability and influence the direction of the entire industry.

Model Specifications

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🚀 Quick Start

Get started with GPT-5.3-Codex API

from openai import OpenAI
client = OpenAI()

response = client.chat.completions.create(
    model="openai/gpt-5.3-codex-20260224",
    messages=[
        {"role": "user", "content": "Hello!"}
    ]
)
print(response.choices[0].message.content)

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