All families

FAMILY / OPENAI

OpenAI o-series

OpenAI’s reasoning line, from the o1 research preview to reasoning with vision and tools.

First model
2024
Models
6
Latest dated version
o4-mini

01 / RELEASE SEQUENCE

Family release sequence

Compare versions →
  1. 2024-09-12o1-miniReasoning · Coding
  2. 2024-09-12o1-previewReasoning · Coding
  3. 2024-12-05o1Reasoning · Multimodal
  4. 2025-01-31o3-miniReasoning · Coding
  5. 2025-04-16o3Reasoning · Coding
  6. 2025-04-16o4-miniReasoning · Coding
6 versions
What changed ↓

02 / GENERATIONS

What changed

01

o1-mini

A smaller reasoning model released alongside o1-preview, focused on coding and mathematics.

02

o1-preview

An early OpenAI reasoning preview designed to spend more computation before answering complex questions.

03

o1

The full o1 release, bringing stronger reasoning and image understanding to ChatGPT.

04

o3-mini

A small text reasoning model for science, mathematics, and coding with selectable reasoning effort; it does not accept images.

05

o3

A reasoning model combining visual reasoning and tool use, released in ChatGPT and the API.

06

o4-mini

An efficiency-focused small reasoning model with vision and tool use.