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OpenAI: 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...

400,000 Context
128,000 Max output
$1.75 / 1M Prompt price
2026-02-24 Created
01 / Snapshot

Pricing, context, modalities, and parameters.

Model Radar detail pages stay neutral and operator-readable: core metadata first, then workflow fit.

Provider OpenAI Input modalities text, image, file
Output modalities text Prompt price $1.75 / 1M
Completion price $14.00 / 1M Request price N/A
Context length 400,000 Max completion tokens 128,000
Supported parameters include_reasoning, max_completion_tokens, max_tokens, reasoning, response_format, seed, structured_outputs, tool_choice, tools
Best for openai/gpt-5.3-codex

OpenAI: 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...

Deep analysis Coding workflows Cross-modal work Long context new vision tool-capable long-context
03 / Colophon

Routes and exits.

Each model page stays simple: overview, compare, related models, then back to the public hub.