Anthropic: Claude Sonnet 4.5 vs OpenAI: o1-pro
Side-by-side comparison of Anthropic: Claude Sonnet 4.5 and OpenAI: o1-pro. Compare pricing, context window, capabilities, and find out which is better for your workflow.
Verdict
strong confidenceAnthropic: Claude Sonnet 4.5 leads overall
Anthropic: Claude Sonnet 4.5 leads in price and context window and capabilities, making it the stronger choice for most workflows. OpenAI: o1-pro remains competitive with advantages in max output.
Best for with Anthropic: Claude Sonnet 4.5
Best for with OpenAI: o1-pro
Side-by-side
Technical specifications
| Anthropic: Claude Sonnet 4.5 | OpenAI: o1-pro | |
|---|---|---|
| Provider | Anthropic | OpenAI |
| Input price | $3/M | $150/M |
| Output price | $15/M | $600/M |
| Context window | 1.0M | 200K |
| Max output | 64K | 100K |
| Capabilities | Tool useVisionReasoning | VisionReasoning |
| Released | Sep 29, 2025 | Mar 19, 2025 |
Scoring breakdown
How each dimension compares
Price
Anthropic: Claude Sonnet 4.5 leadsAnthropic: Claude Sonnet 4.5
$15/M tokens
OpenAI: o1-pro
$600/M tokens
Context Window
Anthropic: Claude Sonnet 4.5 leadsAnthropic: Claude Sonnet 4.5
1.0M tokens
OpenAI: o1-pro
200K tokens
Capabilities
Anthropic: Claude Sonnet 4.5 leadsAnthropic: Claude Sonnet 4.5
3/4
OpenAI: o1-pro
2/4
Max Output
OpenAI: o1-pro leadsAnthropic: Claude Sonnet 4.5
64K tokens
OpenAI: o1-pro
100K tokens
Recency
Anthropic: Claude Sonnet 4.5
Sep 2025
OpenAI: o1-pro
Mar 2025
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