Claude Opus 5.5 vs DeepSeek V4.1 Flash
A direct, empirical evaluation of Claude Opus 5.5 (Anthropic) against DeepSeek V4.1 Flash (DeepSeek-AI).
Claude Opus 5.5
Developed by Anthropic · Proprietary Frontier Reasoner parameters
Autonomous enterprise codebase migrations, GitHub Copilot multi-file edits, SWE-bench Pro issue resolution (89.9%), and CodeRabbit automated reviews.
DeepSeek V4.1 Flash
Developed by DeepSeek-AI · 552B parameters
High-throughput software engineering, autonomous coding loops, terminal agents, 1M long-context retrieval, and low-cost production inference.
| Metric | Claude Opus 5.5 | DeepSeek V4.1 Flash |
|---|---|---|
| SWE-bench Verified | 89.9% | 67.2% |
| MMLU-Pro | 92.4% | 78.4% |
| MATH-500 | 97.2% | 92.6% |
| Context Window | 500,000 tokens | 1,000,000 tokens |
| Input Pricing (per 1M) | $4.00 | $0.06 |
| Output Pricing (per 1M) | $20.00 | $0.22 |