o1-preview
o1-preview is a text generation model from OpenAI that uses internal chain-of-thought reasoning to tackle complex problems.
Chain-of-thought reasoning for hard problems
o1-preview is a large language model developed by OpenAI and released as an early preview of the o1 model series. Unlike standard language models that respond immediately, o1-preview is trained with reinforcement learning to produce an internal chain of thought before generating a final answer, allowing it to work through multi-step problems more methodically. It supports a 128,000-token context window and can generate responses up to 32,768 tokens in length.
The model is designed for tasks that require complex reasoning, including scientific problem-solving, mathematics, and competitive programming. OpenAI reported that o1-series models ranked in the 89th percentile on Codeforces competitive programming questions, placed among the top 500 students in the US on the AIME math qualifier, and exceeded human PhD-level accuracy on the GPQA benchmark covering physics, biology, and chemistry. Note that o1-preview has since been deprecated and succeeded by later models in the o1 series.
What o1-preview supports
Chain-of-Thought Reasoning
Generates a long internal reasoning trace before producing a final response, enabling more accurate answers on multi-step problems.
Math & Science
Designed for rigorous quantitative tasks; o1-series models placed in the top 500 on the AIME qualifier and exceeded PhD-level accuracy on GPQA.
Competitive Programming
Handles complex algorithmic coding challenges; o1-series models ranked in the 89th percentile on Codeforces.
Large Context Window
Accepts up to 128,000 tokens of input, allowing long documents or extensive conversation history to be included in a single request.
Long-Form Output
Supports a maximum response size of 32,768 tokens, suitable for generating detailed analyses, reports, or extended code.
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Get Started FreeCommon questions about o1-preview
What is the context window for o1-preview?
o1-preview supports a context window of 128,000 tokens, meaning it can process up to that many tokens of combined input and conversation history in a single request.
What is the maximum response length for o1-preview?
The model can generate responses of up to 32,768 tokens per reply.
Is o1-preview still available?
No. o1-preview has a deprecated status, meaning it is no longer actively supported and has been succeeded by later models in OpenAI's o1 series.
How does o1-preview differ from standard chat models?
o1-preview is trained with reinforcement learning to produce an internal chain of thought before responding. This means it reasons through problems step by step rather than generating an immediate reply, which is particularly useful for complex scientific, mathematical, and programming tasks.
Does o1-preview support image inputs?
Based on the available metadata, o1-preview does not have confirmed image input support. It is a text generation model.
Parameters & options
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