Claude 3.5 Sonnet (upgraded) vs DeepSeek-V4-Flash
Anthropic Claude 3.5 Sonnet (upgraded) | DeepSeek DeepSeek-V4-Flash | |
|---|---|---|
| Overview | ||
| Company | Anthropic | DeepSeek |
| Release date | Oct 22 2024 | Apr 24 2026 |
| Access | Proprietary | Open Weight |
| Benchmarks | ||
Nonsense detection BullshitBench v2Given a confidently-worded but nonsensical prompt, does the AI spot that it makes no sense and push back — instead of playing along and inventing an answer? The score is how often it clearly called out the nonsense. Higher is better. | — | 18% |
Coding SWE-Bench VerifiedReal coding tasks pulled from open-source projects — the AI has to find and fix actual bugs. A human-checked version of the original SWE-Bench. Higher is better. | 49% | — |
Competitive coding LiveCodeBenchCoding problems published so recently the AI can't have seen them in training — a contamination-free test of raw programming skill. Higher is better. | — | 91.6% |
Science GPQA DiamondGraduate-level science questions in biology, physics, and chemistry — hard enough that subject-matter PhDs score around 65%. Higher is better. | — | 88.1% |
| Timeline | ||
| Release gap | Claude 3.5 Sonnet (upgraded) shipped 549 days before DeepSeek-V4-Flash | |
Which is better: Claude 3.5 Sonnet (upgraded) or DeepSeek-V4-Flash?
Claude 3.5 Sonnet (upgraded) and DeepSeek-V4-Flash don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. Claude 3.5 Sonnet (upgraded) shipped 549 days before DeepSeek-V4-Flash, so benchmark comparisons should account for the intervening progress.
Claude 3.5 Sonnet (upgraded) is proprietary, while DeepSeek-V4-Flash is open weight.
Direct benchmark comparisons are unavailable — Claude 3.5 Sonnet (upgraded) and DeepSeek-V4-Flash don't publish scores on any of the same benchmarks.
Frequently asked questions
Claude 3.5 Sonnet (upgraded) was released by Anthropic on Oct 22 2024.
DeepSeek-V4-Flash was released by DeepSeek on Apr 24 2026.
Claude 3.5 Sonnet (upgraded) is a proprietary model released by Anthropic. DeepSeek-V4-Flash is an open weight model released by DeepSeek.