Claude 3.7 Sonnet vs DeepSeek V4.1 Flash

A direct, empirical evaluation of Claude 3.7 Sonnet (Anthropic) against DeepSeek V4.1 Flash (DeepSeek-AI).

Claude 3.7 Sonnet

Developed by Anthropic · Proprietary parameters

Enterprise software engineering, full-repo refactoring, and agentic workflows.

DeepSeek V4.1 Flash

Developed by DeepSeek-AI · 240B parameters

Real-time production inference, high-concurrency coding agents, sub-220ms time-to-first-token, and cost-optimized long-context parsing.