Comprehensive side-by-side LLM comparison
Claude Sonnet 4.5 leads with 23.0% higher average benchmark score. Claude Sonnet 4.5 offers 103.2K more tokens in context window than o1-preview. Claude Sonnet 4.5 is $57.00 cheaper per million tokens. Claude Sonnet 4.5 supports multimodal inputs. Overall, Claude Sonnet 4.5 is the stronger choice for coding tasks.
Anthropic
Claude Sonnet 4.5 was developed to bridge human thinking and machine assistance, allowing people to work with language and tools in a more conversational and natural way. Built with a focus on turning ideas into results, it represents an evolution in making AI feel less mechanical while maintaining strong capabilities across reasoning, coding, and collaborative tasks.
OpenAI
o1-preview was introduced as an early version of OpenAI's reasoning model series, designed to demonstrate the potential of AI models that engage in extended thinking before responding. Built to solve complex problems through deliberate reasoning processes, it represented an initial step toward more thoughtful and analytical AI systems.
1 year newer

o1-preview
OpenAI
2024-09-12

Claude Sonnet 4.5
Anthropic
2025-09-29
Cost per million tokens (USD)

Claude Sonnet 4.5

o1-preview
Context window and performance specifications
Average performance across 2 common benchmarks

Claude Sonnet 4.5

o1-preview
Performance comparison across key benchmark categories

Claude Sonnet 4.5

o1-preview
Claude Sonnet 4.5
2025-01-31
Available providers and their performance metrics

Claude Sonnet 4.5
Anthropic
ZeroEval


Claude Sonnet 4.5

o1-preview

Claude Sonnet 4.5

o1-preview
o1-preview
Azure
OpenAI