GPT-5 Pro
DeprecatedOpenAI is retiring this model on 11 December 2026. After that date it will not be available for new work.
Thinks hard on every question, with no dial to turn it down. Built for hard problems, not chat or code, and can write very long answers.
- Best for
- Deep reasoning
- Superseded by
- GPT-5.2 Pro
Context window
400,000 tokens
≈ 300,000 words · about 1,200 pages
Max output
272,000 tokens
≈ 204,000 words in a single answer
Knowledge cutoff
September 2024
its training cutoff
Modalities
- TextInput and output
- ImageInput only
- AudioNot supported
- VideoNot supported
Reasoning effort
Default: High.
Features
- StreamingNot supported
- Function callingSupported
- Structured outputsSupported
- Fine-tuningNot supported
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