AI Radar

o1-preview

Retired · Language, Reasoning · Milestone

o1-preview is an OpenAI reasoning model released on 12 September 2024 as an early version of o1 and the first model of the o-series, offered in ChatGPT and to API usage tier 5 developers. OpenAI trained it with large-scale reinforcement learning to work through a chain of thought before answering, and shows users a summary instead of the raw chain of thought. [1] [2] Primary source

Timeline of o1-preview →

Claims and evidence

  • Released Primary source[1]How to use OpenAI o1 [3]Sep 12, 2024
  • Deprecated Primary source[4]2025-04-28: o1-preview and o1-mini
  • Retired Primary source[4]2025-04-28: o1-preview and o1-mini
  • Status Retired Primary source[4]2025-04-28: o1-preview and o1-mini
  • Replaced by o3Recommended replacement listed on the deprecations page when checked on 2026-10-01. Primary source[4]2025-04-28: o1-preview and o1-mini
    • Change · Reasoning Works through a chain of thought before answering, trained with large-scale reinforcement learning; OpenAI says results improve with more time spent thinking.Compared with GPT-4o Primary source[2]
    • Input text Primary source[5]Model details
    • Output text Primary source[5]Model details
    • Context window 128,000 tokens Primary source[5]Model details
    • Parameters Not disclosedNot disclosed by OpenAI. No claim madeNo source
    • Access consumer app, APIChatGPT Plus and Team at launch, Enterprise and Edu the week after; API usage tier 5 only at launch. Primary source[1]How to use OpenAI o1

    Lineage

    Predecessors

    No known predecessor.

    Successors

    • o1 · 5 December 2024

    Based on

    Not derived from another model.

    Variants and derived

    None recorded.

    Siblings

    None recorded.

    All ancestors

    None.

    All descendants

    Variants

    No variants recorded in this record.

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