openai/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.
Scores on standardized evaluations. Higher is better — and rank shows where GPT-5.3 Codex lands among all models tracked on Model Beat.
Novel ML problem-solving
Real GitHub issue resolution
Human-rated web development
Multi-step agentic tasks
Autonomous task length
Command-line agentic tasks
Model & benchmark data from Epoch AI (CC BY); pricing, specs & descriptions from OpenRouter.