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GPT-5.3-Codex
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OpenAIOpenAIGPT Moderated

GPT-5.3-Codex

400K context$1.75/M input$14.00/M output

GPT-5.3-Codex is an AI model from OpenAI built for agent workflows, with support for text, image, file input and text output. 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 an AI model from OpenAI that Agent Mag tracks for pricing, context window, modalities, benchmarks, and API compatibility. Builders can use this page to compare GPT-5.3-Codex against other models for agent workflows and production deployments.

Model ID

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...

Modalities
Input
textimagefile
Output
text
Supported Parameters
include_reasoningmax_completion_tokensmax_tokensreasoningresponse_formatseedstructured_outputstool_choicetools

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