Model releaseLimited global significanceConfirmed confidence
OpenAI releases GPT-5.3-Codex
A closed, developer-focused build that combines GPT-5's general capabilities with OpenAI's advanced code-generation stack.
What happened
Event details
GPT-5.3-Codex is an advanced, development-oriented variant that integrates GPT-5's general capabilities with proprietary code-generation technology. OpenAI released the closed-source model on February 5, 2026; the parameter count is undisclosed and it is an autoregressive Transformer. The primary source is "Introducing GPT-5.3-Codex."
Assessment
Why it matters
Rated on the impact-v1 six-axis scale: technical 2/5, market 2/5, ecosystem 2/5, policy & social 1/5, scope 3/5, durability 2/5.
45/100Global significance score. Regional effects are recorded only when the evidence supports a meaningful difference.