DeepSeek V4 Pro at 5% the cost of Claude – what it takes to close the gap

howardchen.substack.com
June 16, 2026
12 min read
44/100
Summary
DeepSeek V4 Pro is available at 5% of the cost of Claude and offers a range of features including hash-anchored edits, a sticky prefix cache, and autonomous loops for production code. It has been used for various applications such as training dose-prediction models for radiotherapy and developing a financial research agent, with no associated charges.
Key Takeaways
- DeepSeek V4 Pro costs $0.435 per million input tokens, making it 5-7 times cheaper than Claude Sonnet 4, which costs around $3 per million tokens.
- DeepSeek V4 Pro performs at approximately 80-85% of Claude's capability on long tasks, but achieves around 90% effectiveness in practical workflows with custom harness adjustments.
- DeepSeek V4 Pro excels in following precise specifications and producing correct numerical and scientific code, while struggling with long-horizon planning and reading poorly structured code.
- The implementation of hash-anchored editing significantly improved the efficiency of DeepSeek V4 Pro, reducing output tokens by 61% and enhancing performance on coding benchmarks.
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