Overview
o1 is OpenAI's first-generation reasoning model that spends more time thinking before responding. It excels at breaking down complex problems into steps, verifying its work, and catching its own mistakes. The predecessor to o3, still highly capable for demanding reasoning tasks.
Context Window
200K tokens
Knowledge Cutoff
October 2023
Pricing (Input)
$15.00 / 1M tokens
Pricing (Output)
$60.00 / 1M tokens
✅Strengths
- ✓Pioneering deep reasoning architecture
- ✓Excellent at multi-step problem solving
- ✓Self-verification and error correction
- ✓Strong performance on STEM benchmarks
- ✓200K context for complex analysis
⚠️Weaknesses
- ✗Highest latency of all OpenAI models
- ✗Very expensive for production use
- ✗Older knowledge cutoff than o3/GPT-5
- ✗Closed weights - API only
Best Use Cases
🔬 Research
Complex scientific problems
📐 Mathematics
Proofs, competition problems
💻 Code Review
Security audits, architecture
⚖️ Legal
Complex case analysis
🎓 Education
Advanced tutoring, explanations
📊 Strategy
Business planning, analysis
Benchmarks
MMLU93.6%
AIME (Math)93.2%
GPQA (Science)92.4%