GPT-5.3-Codex
OpenAI
GPT-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...
What is GPT-5.3-Codex?
GPT-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...
Specifications
- Developer: OpenAI
- Context window: 400K tokens
- Max output: 128K tokens
- Input modalities: text, image, file
- Output modalities: text
- Input price: $1.75 per 1M tokens
- Output price: $14.00 per 1M tokens
- Knowledge cutoff: —
- Supported parameters: include_reasoning, max_completion_tokens, max_tokens, reasoning, response_format, seed, structured_outputs, tool_choice, tools
Use GPT-5.3-Codex with PromptLayer
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