GPT-5.1 Thinking
OpenAI's advanced reasoning model. Varies thinking time dynamically based on task complexity. Twice as fast on simple tasks, twice as thorough on complex ones.
Pricing
Ratings
Pros
- Best for complex reasoning tasks
- Dynamic thinking time optimization
- Excellent for math and logic
- Great for research and analysis
Cons
- Expensive
- Slower on simple tasks
- Requires Pro subscription
- Writing can feel robotic
Best For
Complex reasoning, math proofs, scientific analysis
Quick Info
- Provider
- OpenAI
- Version
- 5.1
- Released
- Nov 2025
- Context
- 128K tokens
Features
Categories
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