o4 Mini

Deprecated

OpenAI · April 2025

OpenAI is retiring this model on 23 October 2026. After that date it will not be available for new work.

A small, fast reasoning model that works through problems step by step.

Best for: Deep reasoning
Use instead: GPT-5.6 Terra

Context window
200,000 tokens
≈ 150,000 words · about 600 pages
Max output
100,000 tokens
≈ 75,000 words in a single answer
Knowledge cutoff
June 2024
its training cutoff

Modalities

TextInput and output
ImageInput only
AudioNot supported
VideoNot supported

Reasoning effort

Low
Medium
High

Features

StreamingSupported
Function callingSupported
Structured outputsSupported
Fine-tuningSupported

Tools

Web searchSupported
Image generationNot supported
Hosted shellNot supported
Apply patchNot supported
Tool searchNot supported

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