OpenAI releases o3-pro, a souped-up version of its o3 AI reasoning model

OpenAI has launched o3-pro, an AI model that the company claims is its most capable yet.

O3-pro is a version of OpenAI’s o3, a reasoning model that the startup launched earlier this year. As opposed to conventional AI models, reasoning models work through problems step by step, enabling them to perform more reliably in domains like physics, math, and coding.

O3-pro is available for ChatGPT Pro and Team users starting Tuesday, replacing the o1-pro model. Enterprise and Edu users will get access the week after, OpenAI says. O3-pro is also live in OpenAI’s developer API as of this afternoon.

O3-pro is priced at $20 per million input tokens and $80 per million output tokens in the API. Input tokens are tokens fed into the model, while output tokens are tokens that the model generates based on the input tokens.

A million input tokens is equivalent to about 750,000 words, a bit longer than “War and Peace.”

“In expert evaluations, reviewers consistently prefer o3-pro over o3 in every tested category and especially in key domains like science, education, programming, business, and writing help,” OpenAI writes in a changelog. “Reviewers also rated o3-pro consistently higher for clarity, comprehensiveness, instruction-following, and accuracy.”

O3-pro has access to tools, according to OpenAI, allowing it to search the web, analyze files, reason about visual inputs, use Python, personalize its responses leveraging memory, and more. As a drawback, the model’s responses typically take longer than o1-pro to complete, according to OpenAI.

O3-pro has other limitations. Temporary chats with the model in ChatGPT are disabled for now while OpenAI resolves a “technical issue.” O3-pro can’t generate images. And Canvas, OpenAI’s AI-powered workspace feature, isn’t supported by o3-pro.

On the plus side, o3-pro achieves impressive scores in popular AI benchmarks, according to OpenAI’s internal testing. On AIME 2024, which evaluates a model’s math skills, o3-pro scores better than Google’s top-performing AI model, Gemini 2.5 Pro. O3-pro also beats Anthropic’s recently released Claude 4 Opus on GPQA Diamond, a test of PhD-level science knowledge.