OpenAI o1

In plain words

OpenAI o1 is a large language model designed to tackle complex reasoning tasks across general purposes. Trained using reinforcement learning, it generates an internal chain of thought before providing answers, allowing it to work through problems methodically. The model is suited for users who need sophisticated AI assistance with difficult analytical and reasoning-based challenges.

written from the facts on this page · September 2026

From the sources

A new large language model trained with reinforcement learning to perform complex reasoning. o1 thinks before it answers—it can produce a long internal chain of thought before responding to the user.

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