GPT-5.2 Pro

OpenAI · December 2025

Thinks for longer before answering. Built for hard problems, not chat or code.

Best for: Deep reasoning
Superseded by: GPT-5.4 Pro

Context window
400,000 tokens
≈ 300,000 words · about 1,200 pages
Max output
128,000 tokens
≈ 96,000 words in a single answer
Knowledge cutoff
August 2025
its training cutoff

Modalities

TextInput and output
ImageInput only
AudioNot supported
VideoNot supported

Reasoning effort

Medium
High
X-High

Features

StreamingNot supported
Function callingSupported
Structured outputsNot supported
Fine-tuningNot supported

Tools

Web searchSupported
Tool searchNot supported

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