OpenAI: GPT-5.3 Codex
Chatopenai/gpt-5.3-codexGPT-5.3-Codex is OpenAI’s most advanced agentic coding model, combining the frontier software engineering performance of GPT-5.2-Codex with the broader reasoning and professional knowledge capabilities of GPT-5.2. It achieves state-of-the-art results on SWE-Bench Pro and strong performance on Terminal-Bench 2.0 and OSWorld-Verified, reflecting improved multi-language coding, terminal proficiency, and real-world computer-use skills.
Context Window
512K
Max Output Tokens
128K
Released
2026-02-25
Capabilities
VisionFunction CallingReasoningPrompt CachingWeb SearchAudio InputVideo Input
Available Providers
Azure
Supported Protocols
openai
Providers
Azure
Input Tokens
$1.75/M
Output Tokens
$14/M
Cache Read
$0.18/M
Web Search
$0.01/R
Protocols
openai
/v1/responsesCode Examples
from openai import OpenAIclient = OpenAI(base_url="https://api.ofox.ai/v1",api_key="YOUR_OFOX_API_KEY",)response = client.chat.completions.create(model="openai/gpt-5.3-codex",messages=[{"role": "user", "content": "Hello!"}],)print(response.choices[0].message.content)
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Frequently Asked Questions
OpenAI: GPT-5.3 Codex on Ofox.ai costs $1.75/M per million input tokens and $14/M per million output tokens. Pay-as-you-go, no monthly fees.
OpenAI: GPT-5.3 Codex supports a context window of 512K tokens with max output of 128K tokens, allowing you to process large documents and maintain long conversations.
Simply set your base URL to https://api.ofox.ai/v1 and use your Ofox API key. The API is OpenAI-compatible — just change the base URL and API key in your existing code.
OpenAI: GPT-5.3 Codex supports the following capabilities: Vision, Function Calling, Reasoning, Prompt Caching, Web Search, Audio Input, Video Input. Access all features through the Ofox.ai unified API.