OpenAI Releases o3 and o4-mini Reasoning Models

OpenAI is releasing today o3 and o4-mini, its latest reasoning models that can combine every tool within ChatGPT. These two models support web browsing, multimodal understanding, and image generation, and OpenAI says they are the “smartest models” the company has released to date.

“For the first time, our reasoning models can agentically use and combine every tool within ChatGPT—this includes searching the web, analyzing uploaded files and other data with Python, reasoning deeply about visual inputs, and even generating images,” the company explained today. “Critically, these models are trained to reason about when and how to use tools to produce detailed and thoughtful answers in the right output formats, typically in under a minute, to solve more complex problems.”

OpenAI o3 is the new flagship model in the company’s o-series of reasoning models, and the company says that it excels in complex tasks such as programming, business/consulting, and creative ideation. Open o4-mini, however, is a smaller reasoning model with higher usage limits than o3 due to its cost-efficiency. It also has full access to tools within ChatGPT.

Both OpenAI o3 and o4-mini will be available for ChatGPT Plus, Pro, and Team users starting today, and they will replace o1, o3‑mini, and o3‑mini‑high in the model picker. ChatGPT Free users will be able to try o4-mini by selecting ‘Think’ in the composer before submitting their prompt. OpenAI o3 and o4-mini will become available for Enterprise and Edu users in a week, and OpenAI also mentioned the upcoming release of an o3-pro model for the Pro tier in a few weeks.